TN 295 No. 9081 "cv '• V cV" - s • • r , **. if**? V. O N « .V)' ^ ,^A 1 " /,.a'"" ^ ■?>, r *LVL'*^ .......y ^-"W/ \#/ VlSS-V* V™ / V o " o ^ "J- 5> *i^L'* <> o_ * ^. % ■"•O 5 .-"Wff^S,. 'OK >bv c Yfl o i" "T> * w ^O *' '•* **b * o « o « ** 4? >'■ ,6** %, --f.V A V '^?' .0** i9 -k> ^w ii o * :m»o .oy. o -* o y o o' \^^\y V^^'V \ Vt ' ****** ; lSil^ \f «£dM o *w* : M$t£ m ' \^ s^bk* \ ** ; ^fe>'*- \ r y& /\ °*^^ ; ** v \ \^^ ; ^\ °-^P! ; ***\ '-} v • % j. ' . . « * ,.0 "^ <# .'M* ^ >* *®&o u # *^b' ^ / -i^ j0 vv »« ,• » ^ -. H<^ ^4. A* * O o V j0 ^ -^ /*^/ ++/??&+* ° \^^\/ % 3 ^'^ \'W?J IC 9081 Bureau of Mines Information Circular/1986 Thermodynamic Properties of Selected Metal Sulfates and Their Hydrates By Carroll W. DeKock UNITED STATES DEPARTMENT OF THE INTERIOR Information Circular 9081 ■ « Thermodynamic Properties of Selected Metal Sulfates and Their Hydrates By Carroll W. DeKock UNITED STATES DEPARTMENT OF THE INTERIOR Donald Paul Hodel, Secretary BUREAU OF MINES Robert C. Horton, Director As the Nation's principal conservation agency, the Department of the Interior has responsibility for most of our nationally owned public lands and natural resources. This includes fostering the wisest use of our land and water re- sources, protecting our fish and wildlife, preserving the environmental and cultural values of our national parks and historical places, and providing for the enjoyment of life through outdoor recreation. The Department assesses our energy and mineral resources and works to assure that their development is in the best interests of all our people. The Department also has a major re- ibility for American Indian reservation communities and for people who Island Territories under U.S. administration. Library of Congress Cataloging in Publication Data*. DeKock, Carroll W Thermodynamic properties of selected metal sulfates and their hydrates. (Information circular / United States Department of the Interior, Bureau of Mines ; 9081) Bibliography: p. 55-59. Supt. of Docs, no.: I 28.27:9081. 1. Transition metal compounds— Thermal properties. 2. Sulphates- Thermal properties. 3. Hydrates— Thermal properties. I. Title. II. Series: Information circular (United States. Bureau of Mines) ; 9081. TU295AJ4 [TN693.T7] 622s [549\75] 86-600060 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 CONTENTS Page Abstract 1 Unit of measure abbreviations and symbols used in this report 2 Introduction 3 Methods , conventions , and symbols 3 Estimation procedure for hydrates 4 Discussion of thermodynamic properties 4 Ag 2 S0 4 . 4 A1 2 (S0 4 )3 5 A1 2 (S0 4 )3*6H 2 6 BaS0 4 6 BeS0 4 6 BeS0 4 'H 2 f 7 BeS0 4 «2H 2 and BeS0 4 '4H 2 7 CaS0 4 r 7 CaS0 4 «2H 2 0, CaS0 4 *l/2H 2 0(a), and CaS0 4 ' 1/2H 2 0( 3) 8 CdS0 4 8 CdS0 4 «H 2 and CdS0 4 *8/3H 2 8 2CdO • CdS0 4 9 Cs 2 S0 4 9 In 2 (S0 4 ) 3 9 K 2 S0 4 10 KA1(S0 4 ) 2 10 KA1(S0 4 ) 2 «12H 2 10 Li 2 S0 4 10 Li 2 So 4 " T 2 10 MgS0 4 1 MgS0 4 *H 2 1 MgS0 4 «2H 2 and MgS0 4 *4H 2 1 MgS0 4 -6H 2 1 MgS0 4 '7Hi0 1 Na 2 S0 4 1 Na 2 S0 4 *7H 2 1 Na 2 S0 4 *10H 2 12 (NH 4 ) 2 S0 4 12 NH 4 A1(S0 4 ) 2 12 NH 4 A1(S0 4 ) 2 '12H 2 13 PbS0 4 13 Rb 2 S0 4 13 T1 2 S0 4 14 Zr(S0 4 ) 2 14 Thermodynamic tables. — See following listing for specific pages. References 55 THERMODYNAMIC TABLES Ag 2 S0 4 15 A1 2 (S0 4 ) 3 16 Al2(S0 4 ) 3 . 6H20 17 BaS0 4 17 BeS0 4 18 BeS0 4 .H 2 20 BeS0 4 * 2H 2 20 11 THERMODYNAMIC TABLE S— Continued Page BeS0 4 '4H 2 21 CaS0 4 21 CaS0 4 *2H 2 24 CaS0 4 'l/2H20(a) 25 CaS0 4 • 1/ 2H 2 0( 3 ) 25 CdS0 4 26 CdS0 4 'H 2 27 CdS0 4 •8/3H 2 27 2CdO«CdS0 4 28 Cs 2 S0 4 29 In 2 (S0 4 ) 3 31 K 2 S0 4 32 KA1( S0 4 ) 2 34 KA1(S0 4 ) 2 '12H 2 0... 35 Li 2 S0 4 36 Li 2 S0 4 'H 2 0. . . . : 38 MgS0 4 39 MgS0 4 -H 2 42 MgS0 4 -2H 2 43 MgS0 4 '4H 2 43 MgS0 4 »6H 2 44 MgS0 4 '7H 2 44 Na 2 S0 4 45 Na 2 S0 4 • 10H 2 47 (NH 4 ) 2 S0 4 47 NH 4 A1(S0 4 ) 2 48 NH 4 A1(S0 4 ) 2 *12H 2 48 PbS0 4 49 Rb 2 S0 4 50 T1 2 S0 4 52 Zr(S0 4 ) 2 53 THERMODYNAMIC PROPERTIES OF SELECTED METAL SULFATES AND THEIR HYDRATES By Carroll W. DeKock ' ABSTRACT Thermodynamic data for selected metal sulfates were critically evaluated and compiled as part of the Bureau of Mines program to provide a scientific base for use in developing new technology and predicting the feasibility of new processes. Values for Cp°, S°, H° - H| 98 , -(G° - H| 98 )/T, AHf°, AGf°, and log Kf as functions of tem- perature are given in tabular form. Thermodynamic data were compiled for Ag 2 S0 4 , Al 2 (S0 4 )3, Al 2 (S0 4 ) 3 •6H 2 0, BaS0 4 , BeS0 4 , BeS0 4 '2H 2 0, BeS0 4 *4H 2 0, CaS0 4 , CaS0 4 '1/2H 2 0, CaS0 4 *2H 2 0, CdS0 4 , CdS0 4 «H 2 0, CdS0 4 »8/3H 2 0, 2CdO'CdS0 4 , Cs 2 S0 4 , In 2 (S0 4 ) 3 , K 2 S0 4 , KA1(S0 4 ) 2 , KA1(S0 4 ) 2 • 12H 2 0, Li 2 S0 4 , Li 2 S0 4 -H 2 0, MgS0 4 , MgS0 4 *H 2 0, MgS0 4 '2H 2 0, MgS0 4 '4H 2 0, MgS0 4 *6H 2 0, MgS0 4 »7H 2 0, Na 2 S0 4 , Na 2 S0 4 '7H 2 0, Na 2 S0 4 '10H 2 0, (NH 4 ) 2 S0 4 , NH 4 A1(S0 4 ) 2 , NH 4 A1(S0 4 ) 2 -12H 2 0, PbS0 4 , Rb 2 S0 4 , T1 2 S0 4 , and Zr(S0 4 ) 2 . 1 Research chemist, Albany Research Center, Bureau of Mines, Albany, OR; faculty member, Oregon State University, Corvallis, OR. UNIT OF MEASURE ABBREVIATIONS USED IN THIS REPORT atm atmosphere (1 atm = 101,325 pascals) cal thermochemical calorie (1 cal = 4.1840 joules) cal/mol calorie per mole cal/ (mol »K) calorie per mole per kelvin K kelvin (the unit of thermodynamic temperature) kcal/mol kilocalorie per mole mol mole (gram formula weight or molar mass) mol pet mole percent Pa pascal OTHER ABBREVIATIONS AND SYMBOLS USED IN THIS REPORT ° Standard state, pure phase at 1 atm C p Heat capacity at constant pressure F Faraday constant, 23,060.0 cal/(volt*equivalent) AG Gibbs energy change (AGf = Gibbs energy of formation) AH Enthalpy change (AHf = enthalpy of formation) H - H298 Enthalpy increment between T and 298.15 K H-298 ~ Ho Enthalpy increment between 298 and K Log K Logarithm (base 10) of the equilibrium coastant Log Kf Logarithm (base 10) of equilibrium constant of formation P Pressure in atmospheres, 1 atm = 101,325 Pa R Gas constant, 1.98719 cal/(mol«K) S Entropy T Thermodynamic temperature in kelvins INTRODUCTION As part of the Bureau of Mines effort to provide thermodynamic data for mineral technology advancement, thermodynamic properties of selected metal sulfates and their hydrates were critically evaluated and compiled. A 1982 publication compiled similar data on selected transition metal sulfates (11). 2 A number of early reviews of metal sulfates exist (29, _32,, 48). The data for the early reviews are often based on high-temperature sulfate de- composition data. The thermodynamic properties here are calculated on the basis of calorimetric data, many of which were unavailable for the early reviews. No review of the hydrated metal sulfates exists. This compilation has been prepared in the same format as Bureau of Mines Bulle- tin 672, "Thermodynamic Properties of the Elements and Oxides," by L. B. Pankratz (45). The values for the standard heat capacities (Cp), high-temperature relative enthalpies (H° - U^gg), enthalpies of formation (AHf°), and Gibbs energies of forma- tion (AGf°) are given in tabular form. The tables include Gibbs energy functions, -(G° - H298)/T, and logarithms (base 10) of the equilibrium constants of formation, log Kf . Where possible, all phases of an element or compound are presented in a single table. Temperatures of transformations and thermodynamic properties at these temper- atures are included in the table. Immediately below the table, the nature of these transformations is given, along with their associated enthalpies. All thermodynamic values for the elements are from Pankratz (45). METHODS, CONVENTIONS, AND SYMBOLS The values in this compilation are the result of a review and critical evalua- tion of relevant thermodynamic data through July 1984. Standard enthalpies of forma- tion at 298.15 K are corrected to the latest CODATA (7) values where the accuracy of the original data warrants such care. The CODATA value for the standard enthalpy of formation of S0|"(aq) at infinite dilution is the major correction for this document. CODATA gives AHf°(S0|-, »aq) = -217.4 kcal/mol, while Wagman (63) reports AHf°(S0|-, o>aq) = -217.32 kcal/mol. Sulfate ion corrections in this document are based on the CODATA value. Also, AHf°(H 2 0,Jl) = -68.315 kcal/mol, used throughout this review, is from Wagman (63). The selected experimental data were fitted to a polynomial in terms of tempera- ture by using a modified form of the computer program described by Justice (28). This program, along with a plot of function (H° - H.2 98 )/(T - 298.15), which takes a known value of Cp° at 298.15 K, was used to merge high-temperature data smoothly with low-temperature heat capacity data. The resulting polynomial was then used in a subroutine of the program to calculate standard heat capacities, relative enthal- pies, Gibbs energy functions, and standard entropies at selected temperatures. In addition, the thermodynamic tables include values for the standard enthalpy of ^Underlined numbers in parentheses refer to items in the list of references at the end of this report. formation, Gibbs energy of formation, and the logarithm of the equilibrium constant of formation. Tabulated values are given for the substances in their standard states (indicated by the superscript "°"). Sources of data used in this compilation are given in the list of references; additional sources reviewed and considered less reliable are not included. Estimates are used where the necessary data were lacking, as explained in the section on esti- mation procedures. Estimated and extrapolated values are indicated in the note below each table. The common practice of tabulating five- and sometimes six-digit values has been followed. For example, enthalpy values are given to the nearest calorie. The number of digits given is not intended to reflect the accuracy of the experimental values used, but rather to produce internal consistency in the tables. In the text, values are given to the significant figures to which they are thought to be accurate. ESTIMATION PROCEDURES FOR HYDRATES The same estimation procedures were used as in the first compilation in this se- ries (11) for hydrates for which data were unknown. Briefly, the estimation methods are as follows: Heat capacities for hydrates were estimated by adding 9.3 cal/ (mol»K) per mole H 2 to the heat capacity of the anhydrous compound to obtain the heat capacity at 298.15 K. The entropy of the hydrates at 298.15 K was estimated by adding 9.5 cal/(mol»K) per mole H 2 to the entropy of the anhydrous compound at 298.15 K. Other estimation procedures, tailored for individual compounds, are dis- cussed in the text. With the values at 298.15 K in hand, it was then necessary to estimate the heat capacities above 298.15 K. For hydrates for which low-temperature data are avail- able, heat capacities up to 550 K were estimated by extrapolating the low-temperature data, using a least-squares fit with the quadratic equation, Cp = a + bT + cT 2 . For salts for which data are not available, high-temperature heat capacities were esti- mated using the following equation: Cp(T) = Cp(298.15) + b(T-298.15), where b is a coefficient dependent on n, the number of water molecules. The values calculated for b are — 1 0.09 2 .10 3 .132 4 .144 5 0.180 6 .216 7 .252 DISCUSSION OF THERMODYNAMIC PROPERTIES Ag 2 S0 4 (c) The values from Parker ( 50 ) for the enthalpy of formation and entropy at 298.15 K are adopted. Ag 2 S0 4 exists in the orthorhombic form at ambient temperature and transforms to the Na 2 S0 4 (I) structure at 698.6 K ( 27 , 42). Low-temperature heat capacity values have been measured by Latimer (40). Heat capacity values measured by Shmidt (57) from 299.2 to 727.6 K using an adiabatic calorimeter were merged with the low-tempeir- ture values of Latimer (40). Conard (9) measured high-temperature enthalpy values over the range 568 to 1,025 K using a drop calorimeter. The results of Conard do not merge well with those of Shmidt (57). Also the values of Conard scatter badly. For these reasons the values of Shmidt ( 57 ) for the transition enthalpy and temperature were adopted. Shmidt determined the transition temperature to be 698.6 K with an enthalpy of transition equal to 3.901 kcal/mol. An enthalpy of transition equal to 3.8 kcal/mol and a transition temperature of 700 K were determined in this laboratory by differential scanning calorimetry. 3 These values are in good agreement with those of other workers using differential thermal analysis. Hedvall (25) observed a tran- sition enthalpy of 3.8 kcal/mol. Others (9_, 25 ) have reported a transition tempera- ture of 703 K. Conard (9) found a melting point of 926 K with an enthalpy of fusion equal to 4.56 kcal/mol. These values are adopted here. Their average heat capacity value for the liquid was 35 cal/(mol*K), which is the adopted value. Al 2 (S0 4 ) 3 (c) Low-temperature heat capacity data are given by Shomate (58) from 54.7 to 296.2 K. An excellent fit of these data was obtained using the appropriate polyno- mial equations from which the entropy and enthalpy over the range 53 to 298.15 K were obtained. The entropy and enthalpy from to 53 K were obtained from the function sum given by Shomate (58) to represent the heat capacities over the entire tempera- ture range: D(155.7/T) + 3E(238/T) + 6E(528/T) + 6E(1,194/T). The symbols D and E denote, respectively, Debye and Einstein functions. There is excellent agreement between the present data analysis and that of Shomate (58), as shown below for entropies at 298.15 K for A1 2 (S0 4 )3: Shomate This wor k to 53 K 3.76 3.77 53 to 298.15 K 53.43 53.45 S°(298.15) 57.19 57.22 The above entropy values at 298.15 K are both rounded to 57.2 cal/(mol«K). The high-temperature enthalpy values were taken from Shomate (59). The standard enthalpy of formation at 298.15 K is from Wagman (63) , corrected for the enthalpy of formation of the sulfate ion at infinite dilution. 3 The author thanks Robert R. Brown, research chemist, Albany Research Center, Al- bany, OR 97321, for performing the differential scanning calorimeter measurements on various compounds. Al 2 (S0 4 )3-6H 2 0(c) Low-temperature heat capacities are given by She-mate ( 58 ) from 54.5 to 296.1 K. An excellent fit of these data was obtained using the appropriate polynomial equa- tions from which the entropy and enthalpy over the range 53 ro 298.15 K were obtained from the computer subroutine programs. The entropy and enthalpy from to 53 K were obtained from the function sum given by Shomate to represent the heat capacities over the entire temperature range: D(78.9/T) + 3E(142.5/T) + 8E(340/T) + 16E(872/T). Good agreement exists between the present data analysis and that of Shomate as shown below for entropies at 298.15 K for A1 2 (S0 4 ) 3 *6H 2 0: Shomate This work to 53 K... 11.23 11.24 53 to 298.15 K 100.88 100.95 S°(298.15) 112.09 112.19 Accordingly 112.2 cal/(mol*K) was added as the entropy at 298.15 K. The high-temperature enthalpy values were obtained by extrapolating the low- temperature data between 206.2 to 296.5 K using a quadratic polynomial. The standard enthalpy of formation at 298.15 K is from Wagman (63) , corrected for the enthalpy of formation of the sulfate ion at infinite dilution. BaS0 4 (c) Parker's ( 49 ) enthalpy of formation for BaS0 4 (c), after correction for the enthalpy of formation of the sulfate ion at infinite dilution, was adopted. The entropy of BaS0 4 (c) at 298.15 K was recalculated from the low-temperature heat capacity data of Latimer (39). Latimer estimated the entropy at 20 K to be 0.379 cal/(mol*K), which is adopted here, and calculated S 298 [BaS0 4 (c) ] = 31.5 cal/(mol*K). Recalculation of the data gave S 298 [BaS0 4 (c) ] = 31.6 cal/(mol»K), which is the value reported by Parker (49). This evaluation also gave [H 298 - H ° ] = 4.584 kcal/mol. The only high-temperature enthalpy study is that of Lashchenko (36) over the range 293 to 1,323 K. These data were only used above 600 K because the lower tem- perature data had severe scatter. The low-temperature heat capacity data of Latimer (39) were extrapolated to 500 K and joined smoothly with the high-temperature data. BeS0 4 (c) Navratil (44) determined the enthalpy of formation of BeS0 4 (c) by sulfuric acid solution calorimetry. The value was obtained in a careful study that involved three separate Be samples and two different sulfuric acid solutions. Recalculated using the CODATA (7) S0|~ value, the Navratil value yields AHf 298 [BeS0 4 (c) ] = -287.08 kcal/mol. This value is adopted. The value in Parker (48) for AHf 298 [BeS0 4 (c) ] is -288.05 kcal/mol. Low-temperature heat capacity values, high-temperature enthalpies, and the entropy at 298.15 K were those adopted by JANAF (15). BeS0 4 'H 2 0(c) From a study of the vapor pressure of BeS0 4 (c) + H 2 Q, Broers (_5-j>) determined AH°(298.15 K) = 16.27 kcal/mol for the reaction BeS0 4 «H 2 0(c) = BeS0 4 (c) +H 2 0(g). Using the adopted AH values for BeS0 4 (c) and H 2 0(g) gives AHf 298 [BeS0 4 *H 2 0(c) ] = -361.15 kcal/mol. This value is adopted. Parker (49) gives AHf 298 [BeS0 4 'H 2 0] = -364.2 kcal/mol. Broers (.5-6) also obtained S 298 [BeS0 4 'H 2 0] = 28.91 cal/(mol»K) and estimated C° = 28.56 cal/(mol*K). These values are adopted. The high-temper- ature heat capacity dependence was estimated as discussed earlier. BeS0 4 «2H 2 0(c) and BeS0 4 '4H 2 0(c) Navratil (44) recalculated the enthalpies of formation for BeS0 4 *2H 2 0(c) and BeS0 4 •4H 2 0(c) obtained by Taylor (62) in the study of the enthalpies of formation of BeS0 4 (c) and the respective hydrates. After correction for the enthalpy of formation for S0^ _ Navratil' s (44) recalculated values are AHf 298 [BeS0 4 «2H 2 0(c) ] = -434.78 kcal/mol and AHf 298 [BeS0 4 *4H 2 0(c) ] = -578.38 kcal/mol. These values are adopted. Parker (49) gives AHf 298 [BeS0 4 -2H 2 0] = -435.74 kcal/mol and AHf 298 [BeS0 4 '4H 2 0] = -579.29 kcal/mol. Low-temperature heat capacity values and entropy values are taken from Gardner (23). High-temperature heat capacities were obtained by extrapo- lation of the low-temperature values. CaS0 4 (c) There are three recognized forms of anhydrous calcium, sulfate: insoluble anhy- drite, (i), and two forms of soluble anhydrite, (a) and (3). The enthalpies of for- mation for all three forms are taken from Parker (49) after correction for the en- thalpy of formation of the sulfate ion. All entropy values were reevaluated using the low-temperature heat capacity data of Kelley (31). Debye-Einstein function sums are given by Kelley for each form of anhydrous CaS0 4 . These were used to extrapolate the entropy and enthalpy from K to approximately 50 K. The function sums for each of the forms are — CaS0 4 (i): D(208/T) + 2E(300/T) + 2E(815/T) CaS0 4 (ct): D(217/T) + 2E(278/T) + 2E(821/T) CaS0 4 (g): D(286/T) + 2E(246/T) + 2E(844/T) The calculated entropy values are compared below with those reported by Kelley. CaS0 4 (i) CaS0 4 (q) CaS0 4 (g ) S° (50.1) (Kelley) S°(50.1)(This work) S°(298) - S°(50.1)(Kelley) S°(298) - S°(50.1)(This work) S°(298)(Kelley) S°(298)(This work) 1.51 1.76 1.57 1.655 1.89 1.48 23.95 24.17 24.33 23.96 24.16 24.24 25.5 25.93 25.90 25.62 26.05 25.72 It is clear from the above tabulation that the entropy calculated by either method is in good agreement between 50.1 and 298.15 K for both CaS0 4 (i) and CaS0 4 (a). For CaS0 4 (g) a difference of 0.09 cal/(mol»K) exists is this region. This is very good considering the method of calculation, i.e. , Kelley determined the entropy by a graphical method, while in this work the entropy is determined by a least-squares analytical fit of the heat capacity data with a subsequent subroutine generating en- tropy. Kelley's (31) De bye-Einstein functions were used for the extrapolation from to 50.1 K, yet in all cases the two sets differ by 0.1 cal/(mol # K) in an apparently random manner. In this work the value of the entropy calculated from the Debye- Einstein functions from to 50.1 K was determined using a computer program that had been carefully checked against other data. At present it is uncertain why Kelley's (31) extrapolated values differ so significantly from those reported here. The high-temperature enthalpy values for all three forms were taken from Lash- chenko (37-38). The data scatter badly at the lower temperatures. Accordingly, some of the lower values were deleted in the analysis. CaS0 4 «2H 2 0(c), CaS0 4 * l/2H 2 0(a,c) , and CaS0 4 •l/2H 2 0(e ,c) Three hydrates of calcium sulfate are considered here: CaS0 4 *2H 2 0(c) , CaS0 4 •l/2H 2 0(a,c), and CaS0 4 »l/2H 2 0(3 ,c) . The definitive work on the hydrates of calcium sulfate still remains that of Kelley published in 1941 (31). The enthalpies of formation and entropies at 298.15 K for all the compounds were taken from Parker (49). Heat capacity values were extrap- olated to 550 K by the methods discussed in the introduction, using the heat capacity data from Kelley (31) for the hemihydrates and the data from Latimer (39) for the di- hydrate. The data below 298.15 K for the dihydrate were obtained by fitting the heat capacity data of Latimer ( 39 ) to a polynomial and calculating the entropy and enthal- py at the temperatures of interest. The fit in the present work yielded S°(298) - S°(19.95) = 46.062 cal/(mol*K), while the entropy reported by Latimer ( 39 ) over the same temperature interval was 46.096 cal/(mol # K) obtained by a graphical method. CdS0 4 (c) Adami (JL_) found the enthalpy of the reaction CdO(c) + H 2 SO 4 '7.068H 2 O(l) = CdS0 4 (c) + 8.068 H 2 0(1) to be AH = -20.140 kcal by hydrochloric acid solution calorimetry. CODATA (_7_) re- ports AHf 298 [CdO(c)] = -61.7 kcal/mol. Wagman ( 63 ) gives AHf 298 [H 2 S0 4 '7.068H2O] = -209.566 kcal/mol after making the sulfate correction. These values give AHf 298[CdS0 4 (c) ] = -223.09 kcal/mol, which is the adopted value. Low-temperature (15.22 to 312.81 K) heat capacities and entropies are those reported by Papadopoulos (47). No high-temperature enthalpy data are available; however, the data were esti- mated above 300 K using the high-temperature enthalpy data for ZnS0 4 (c) (11). CdS0 4 'H 2 0(c) and CdS0 4 -8/3H 2 0(c) The enthalpies of formation for both CdS0 4 *H 2 and CdS0 4 # 8/3H 2 were taken from Wagman (63) after making the sulfate correction. Heat capacities (15 to 300 K) and entropies are from Papadopoulos (47). High-temperature data were estimated by ex- trapolating the low-temperature heat capacities to 550 K. 2CdO'CdS0 4 (c) Beyer (j4) measured the heat capacity of cadmium oxy sulfate, 2Cd0*CdS0 4 , from 5.16 to 300.7 K by adiabatic calorimetry. The relative enthalpy was measured to 1,001.5 K by copper-block drop calorimetry. A nonisothermal transition was observed over the temperature range 245 to 260 K with a peak at 253 K. The value at 298.15 K for [H? - H°] = 8.604 kcal/mol. Ko (33), using HC1 solution calorimetry, found AHf 298 [2CdO»CdS0 4 (c) ] = -345.70 kcal/mol. This value is adopted. This is to be compared with Schaefer (55) , who calculated a third-law value from electrochemical cell measurements, AHf 2g8 [2Cd0 •CdS0 4 (c)] = -344.4 kcal/mol, in good agreement with the value reported by Ko (33). Cs 2 S0 4 (c) The enthalpy of formation, AHf 298 [Cs 2 S0 4 ] = -344.97 kcal/mol, is from Wagman ( 65 ) after correction for the enthalpy of formation of the sulfate ion at infinite dilution. The low-temperature heat capacities of Cs 2 S0 4 were measured by Paukov (51) over the range 12.82 to 308.72 K. The adopted value for S| 98 = 50.64 cal/(mol*K) and the value for [H 2 9 8 - H°] = 6.628 kcal are those reported by JANAF ( 18 ) in their evalua- tion of Paukov' s ( 51 ) data. High-temperature heat capacities have been measured by Shmidt (56) over the range 297.5 to 774.0 K. Denielou (12-14) carried out high- temperature enthalpy measurements by drop calorimetry over the range 400 to 910 K. The low-temperature heat capacities of Paukov ( 51 ) were joined with the high-temper- ature heat capacities of Shmidt (56) to provide enthalpy values which were merged with the enthalpy values of Denielou (12-14) above 700 K. JANAF (18) adopted a transition temperature of 940 K with an enthalpy of transi- tion of 1.030 kcal/mol, based on the difference between the smooth enthalpy curves of the high- and low-temperature modifications. A transition temperature of 997 K and an enthalpy of transition value of 0.072 kcal/mol were determined in this laboratory by differential scanning calorimetry. The present work adopts the latter values for the enthalpy and temperature of transition for Cs 2 S0 4 . This transition is very simi- lar to that for Rb 2 S0 4 . See the discussion of the Rb 2 S0 4 system. The melting point is that adopted by JANAF ( 18 ) at 1,278 K, and the enthalpy of fusion is calculated to be 8.47 kcal/mol from the difference in the smoothed enthalpy curves between the liquid and the solid forms. In 2 (S0 4 ) 3 (c) Barany (2) determined the enthalpy of formation to be AHf 298 [In 2 (S0 4 ) 3 (c) ] = -651.34 kcal/mol, using solution calorimetry. This value includes the correction for the enthalpy of formation of the sulfate ion. Low-temperature heat capacity data for anhydrous indium sulfate were reported by Pankratz (46) from 52 to 296 K. A reevaluation of these data, including a recal- culation of the De bye-Einstein function sums, yielded S 298 [In 2 (S0 4 ) 3 ] = 72.24 cal/ (mol'K). This is good agreement with Pankratz's analysis, which yielded 72.2 cal/(mol«K). 10 High-temperature enthalpies were also obtained from Pankratz (46). An excellent fit between low- and high-temperature heat capacities were observed. K 2 S0 4 (c) All data for K 2 S0 4 are taken from JANAF (16). KAl(S0 4 ) 2 (c) Wagman ( 65 ) reported AHf 298 [KAl(S0 4 ) 2 (c) ] = -590.56 kcal/mol after correction for the enthalpy of formation of the sulfate ion. This value is adopted. A recalcu- lation of the data from Kelley (30) yielded AHf 298 [KAl(S0 4 ) 2 (c) ] = -590.46 kcal/mol, in good agreement with the value reported by Wagman (65). Low-temperature heat capacity values were reported by Kelley ( 30 ) in the range 54.6 to 296.5 K. These data were reevaluated, including a recalculation of the De bye-Einstein function sums, to obtain S 298 [KAl(S0 4 ) 2 (c) ] = 48.94 cal/(mol'K). Kel- ley 's (30) analysis yielded S 298 [KAl(S0 4 ) 2 (c) ] = 48.9; Wagman (65) also reports S 298 [KAl(S0 4 ) 2 (c)] = 48.9 cal/(mol*K). A smooth fit between the low- and high-temperature heat capacity data was ob- tained by giving a weight of zero to the 368.5 K point reported by Kelley (30). High-temperature heat capacities and entropies were calculated from a smooth fit of the remaining high-temperature enthalpy data (30). KAl(S0 4 ) 2 -12H 2 0(c) The enthalpy of formation reported by Wagman (65) is AHf 298 [KA1(S0 4 ) 2 * 12H 2 0(c) ] = -1,448.96 kcal/mol after correction for the enthalpy of formation of the sulfate ion. This value is identical to that obtained from Kelley (30) using values from the present work for the enthalpy of formation of K 2 S0 4 and Al 2 (S0 4 ) 5 *6H 2 0, together with the accepted value for the enthalpy of formation of water. The entropy at 298.15 K is from Wagmen (65). Low-temperature heat capacities from Shomate ( 58 ) were matched with the heat capacities reported by Gronvold (24) in the region 298.15 to 358.99 K. The transition enthalpy for KA1(S0 4 ) 2 •12H 2 0(c) to KA1(S0 4 ) 2 »3H 2 plus aqueous solution at 358.99 K is reported by Gronvold (24) to be 22.8 kcal.mol. Li 2 S0 4 (c) All data for Li 2 S0 4 (c) are taken from JANAF (17). Li 2 S0 4 »H 2 0(c) The enthalpy of formation of Li 2 S0 4 *H 2 0(c) was determined by Barany (_3) using hydrochloric acid solution calorimetry. Recalculation of the results using auxiliary data from CODATA (_7) and Wagman (63) yields AHf 298 [Li 2 S0 4 *H 2 0] = -414.53 kcal. This value is adopted. Low-temperature heat capacities have been measured by Paukov (53) from 13.87 to 300.74 K. Paukov's calculated value for S 298 is 34.995 cal/(mol«K), which is adopted here. The value reported by Wagman (65) , 39.1 cal/(mol*K), appears to be in error. The heat capacity values above 298.15 K were obtained by extrapola- tion of the low-temperature values of Paukov (53). 11 MgS0 4 (c) Until recently, the enthalpy of formation values for MgS0 4 (c) were quite uncer- tain. For example, JANAF (15) selected AHf 2 98[MgS0 4 (c) ] = -301.6 kcal/mol, while Parker (49) gave -307.1 kcal7mol; other values reported were -313.0 kcal/mol by Kel- ley (29) and -310.0 kcal/mol by Lau (41) . MgS0 4 (c) exists in two orthorhombic crys- talline forms, MgS0 4 (a) and MgS0 4 (3) (80. The above-reported values for the enthalpy of formation make no reference to the crystalline form of MgS0 4 . In an effort to clarify the enthalpy of formation value for MgS0 4 , Ko ( 34 ) prepared both forms of MgS0 4 and determined their enthalpies of formation by hydrochloric acid solution cal- orimetry. The values are AHf ^ 98 [MgS0 4 (a) ] = -308.03 kcal/mol and AHf | 98 [MgS0 4 (3)] = -307.11 kcal/mol after correcting for the enthalpy of formation of the sulfate ion. Heat capacities, entropies, and high-temperature enthalpies are taken from JANAF (15). MgS0 4 -H 2 0(c) Correcting the value of Ko (34) for the enthalpy of formation of the sulfate ion yields AHf 298 [MgS0 4 *H 2 0(c) ] = -384.80 kcal/mol. This value was determined in the same study as the above values for a- and 3 _ MgS0 4 (c). The heat capacity at 9° C was determined by Rolla (54) to be 33.2 cal/(mol*K). The heat capacity values in the MgS0 4 *H 2 table are estimates based on the value by Rolla. The entropy at 298.15 K is from Parker (49) . MgS0 4 «2H 2 0(c) and MgS0 4 »4H 2 0(c) The enthalpies of formation are from Parker (49) after making the SOf" correc- tion, while the heat capacities and entropies are estimates. The enthalpy of forma- tion, AHf 2 9s[MgS0 4 # 2H 2 0(c) ] = -453.3 kcal/mol, appears to be too positive for the required stability of the dihydrate with respect to the monohydrate. MgS0 4 «6H 2 0(c) The enthalpy of formation is from Parker ( 49 ) after making the S0|~ correction, while the low-temperature heat capacities and entropy values are from Cox ( 10 ) . The heat capacity values above 320 K were obtained by extrapolation of the low- temperature values . MgS0 4 -7H 2 0(c) The enthalpy of formation at 298.15 K after making the S0|~ correction and en- tropy at 298.15 K are from Parker (49) . The heat capacity at 9° C was determined by Rolla (54) , and the heat capacity values given in the MgS0 4 *7H 2 table are estimates based on their value. Na 2 S0 4 (c) All data for Na 2 S0 4 (c) are taken from JANAF (16). Na 2 S0 4 -7H 2 0(c) Gans (22) , from equilibrium vapor pressure measurements, has established the existence of the heptahydrate as an independent stable phase. The upper temper- ature limit for coexistence with the saturated aqueous solution is 296.61 K for the 12 heptahydrate. Gans values are AHf 2 98[Na 2 S0 4 *7H 2 0] = -826.96 kcal/mol and S| 98 [Na 2 S04-7H 2 0] = 98.47 cal/(mol*K). Na 2 S0 4 »10H 2 0(c) The enthalpy of formation, after the sulfate correction, and entropy are taken from Wagman (65). The temperature dependence of the heat capacity was estimated us- ing the method discussed in the introduction. Gronvold (24) reported that the peri- tectic transition to Na 2 S0 4 (c) and aqueous solution occurs at 305.533 K with an en- thalpy of 18.65 kcal/mol. (NH 4 ) 2 S0 4 (c) The enthalpy of formation is from Parker ( 50 ) after making the S0|" correction. The low-temperature heat capacity values from 52.7 to 295.4 K and high-temper- ature enthalpies from 402 to 640 K were reported by Kelley ( 30 ) . The entropy at 298.15 K was recalculated from the low-temperature heat capacity data (30) . TheDebye-Einstein function sum given by Kelley ( 30 ) for (NH 4 ) 2 S0 4 (c) up to 150 K is D(121.7/T) + 2E(201/T) + 4E(472/T) + 8E(1,090/T). This function sum gave S°(50.12) = 4.58 cal/(mol*K). The data from 50.12 to 190 K were fit with a polynomial, which resulted in an entropy of 26.71 cal/(mol«K) in this region. Kelley ( 30 ) reports a transition at 233.4 K with an entropy change of 10.47 cal/(mol*K) in the region 190 to 230 K. The data from 230 to 298.15 K were fit with a polynomial, yielding an entropy change of 10.95 cal/(mol*K) in this inter- val. The total yields S 2 98 = 52.71 cal/(mol # K), which is the adopted value. This value is also reported by Parker (50) . This compares with S 298 = 52.6±0.3 cal/ (mol*K) reported by Kelley (30) from analysis of the same data. The slopes of the low-temperature heat capacity data and the heat capacities ob- tained from the high-temperature enthalpy data did not match smoothly. A good match was obtained by eli.minating the points at 402.1 K and 639.6 K and weighting the low- temperature data appropriately. NH 4 Al(S0 4 ) 2 (c) The enthalpy of formation of NH 4 A1(S0 4 ) 2 is reported by Wagman (63) , after mak- ing the sulfate correction, to be AHf 2 93[NH 4 A1(S0 4 ) 2 ] = -562.36 kcal/mol. Kelley (30) reports AHf 2 98[(NH 4 )A1S0 4 ) 2 ] = -561.15 kcal/mol, which was recalculated using our adopted values for enthalpy of formation of (NH 4 ) 2 S0 4 and A1 2 (S0 4 ) 3 , 6H 2 0, giving a value of AHf 298 [NH 4 A1(S0 4 ) 2 ] = -562.46 kcal/mol. The average of these two, -562.4 kcal/mol, is adopted. Low-temperature heat capacity values from 54.7 to 296.2 K are reported by Kelley (30) . High-temperature enthalpy measurements from 377.9 to 698.7 K are also reported by Kelley (30). The entropy at 298.15 K was recalculated on the basis of the low-temperature heat capacity data of Kelley (30) . The Debye-Einstein function sum given by ( 30 ) for NH 4 A1(S0 4 ) 2 is 13 D(165.2/T) + 3E(248/T) + 5E(538/T) + 5E(1,216/T). This function sum gave S°(53.09) = 3.39 cal/(mol»K), very close to Kelley's 3.37 cal/(mol*K) (30) . The recalculated entropy is S| 98 = 51.71 cal/(mol°K), which is identical with - " that reported by Kelley (30) . The above evaluation also gave [H 298 - H°] = 8.629 kcal/mol at 298.15 K. NH 4 Al(S0 4 ) 2 -12H 2 0(c) The enthalpy of formation, AHf 298 [NH 4 A1(S0 4 ) 2 ' 12H 2 0(c) ] = -1,420.42 kcal/mol, is from Wagman ( 63 ) , corrected for the enthalpy of formation of the sulfate ion. This value compares - well with AHf ° [NH 4 A1(S0 4 ) 2 «12H 2 0] = -1,420.59 kcal/mol, which is based on a recalculation of the data given in Kelley ( 30 ) . The heat capacity values are from Gronvold (24) merged with values to 296 K from Kelley ( 30 ) . Gronvold ( 24 ) also reports that the enthalpy of fusion of NH 4 Al(S0 4 )-12H 2 0(c) at 367.13 K is 29.16 kcal/mol. The entropy at 298.15 K is from Wagman (63). PbS0 4 (c) The enthalpy of formation and entropy at 298.15 K are from CODATA (7). H 298 - Hq is also taken from CODATA (7_) . High-temperature enthalpy values were taken from data by Krestovnikov (35) , who obtained data over the range 288 to 1,073 K by drop calorimetry. Krestovnikov 's values were fit smoothly to the low-temperature heat ca- pacity data of Gallagher ( 21 ) . Comparison of log Kf values for PbS0 4 obtained from solid state emf determina- tions by Fredriksson (20) show close correspondence between the calculated and exper- imental values : log Kf(PbS0 4 ) T/K Ref(20) This work 1,000 28.43 28.51 1,100 23.95 23.91 It is gratifying to see this close correlation between data arrived at by calorimet- ric measurements (our calculations) and emf high-temperature measurements (20). Rb 2 S0 4 (c) The enthalpy of formation AHf 2 98 [Rb 2 S0 4 ] = -343.12 kcal/mol is from CODATA (7). The low-temperature heat capacity from 12.54 to 303.12 K was measured by Paukov (52). Paukov's calculated entropy at 298.15 K is S 298 [Rb 2 S0 4 ] = 47.19 cal/(mol«K), which is adopted here. High-temperature heat capacities from 298.15 to 770.5 K have been measured by Shmidt (56) , while Denielou (12-14) has measured the high-temper- ature enthalpy from 274 to 1,466 K. Both Ingraham (26) and Denielou (12-14) report a first-order transition at 931 K with transition enthalpies of 2.11 kcaTTmol and 1.039 kcal/mol, respectively. The enthalpy of transition was measured in this laboratory by differential scanning calorimetry (DCS) and found to be far smaller than orig- inally reported. The measured value is 0.104±0.01 kcal/mol in the region 925 to 14 938 K. The DSC data show an anomalous increase in the heat capacity beginning at about 825 K with a very small first-order component at 931 K. The data of Denielou (12-14) show this anomalous effect, which they ignored in their interpretation. The same effect is noted for Cs 2 S0 4 . The low-temperature data of Paukov (52) were smoothly merged with the high- temperature data of Shmidt (56) by fitting the data to orthogonal polynomials. The data of Denielou (12-14) were not used in the region 298 to 770 K because they did not merge well with the low-temperature data of Paukov ( 52 ) . The enthalpy data of Denielou (12-14) above 770 K, however, were merged with the data of Shmidt ( 56 ) to obtain the enthalpy to 931 K. Above 931 K, the data of Denielou (12-14) were avail- able. The data in the liquid region were smoothly extrapolated to 2,000 K using a heat capacity for the liquid of 49.33 cal/(mol*K). The enthalpy of fusion AH^ = 9.180 kcal/mol is adopted from Denielou (12-14) . Our enthalpy values in the region above 931 K were identical to those of Denielou (12-14) . Tl 2 S0 4 (c) The entropy and enthalpy of formation at 298.15 K are from Wagman ( 63 ) after correction for the enthalpy of formation of the sulfate ion. Shmidt ( 57 ) measured the heat capacity of TI2SO4 using an adiabatic calorimeter over the temperature range 298.4 to 582.8 K. These results were fitted smoothly with the high-temperature en- thalpy data of Dworkin ( 19 ) taken with a drop calorimeter. Their data span the tem- perature range 400.2 to 901.1 K for solid and 922.2 to 988.3 K for the liquid. They found the orthorhombic-to-hexagonal transition to occur at 774 K with an enthalpy of 0.160 kcal/mol. The melting point was found to be 916 K with an enthalpy of fusion equal to 5.870 kcal/mol. These values are adopted. For the liquid segment, a con- stant heat capacity of 49 cal/(mol*K) was adopted on the basis of the enthalpy values reported by Dworkin (19) . Zr(S0 4 ) 2 (c) The standard enthalpy of formation has been measured by Melnikova ( 43 ) by hydro- chloric acid solution calorimetry. The enthalpy change of the reaction Zr(S0 4 ) 2 *0.03S0 3 (c) + 4KCl(c) + 0.03H 2 )(1) = ZrCl 4 (c) + 2K 2 S0 4 (c) + 0.03H 2 S0 4 (soln) was found to be AHr = 116.15 kJ(27.76 kcal) . The standard enthalpy of formation can be calculated using AHf £ 98 [ZrCl 4 ] = -234.35 kcal/mol (64), AHf 298 [K 2 S0 4 ] = -343.62 kcal/mol U6 ) , AHf 298 [H 2 S0 4 -800H 2 0] = -213.208 kcal/mol (63), AHf 298 [KCl] = -104.385 kcal/mol (65), and AHf 298 [H 2 0] = -68.315 kcal/mol ( 63J . Combining the above values yields AHf 2 98[ a-Zr (S0 4 ) 2 (c) ] = -536.16 kcal/mol, which is the adopted value. This value is compared with AHf 2 98[Zr(S0 4 ) 2 ] = -529.9 kcal/mol reported by Wagman (64). Stern ( 61 ) estimated S 298 [Zr(S0 4 ) 2 ] = 31.8 cal/(mol*K). High-temperature en- thalpy values to 1,050 K have been measured by Smith (60) using an ice calorimeter. 15 [Formation: Ag 2 S0 4 (c) Silver sulfate 2Ag(c) + S(c,l) + 2 2 (g) = Ag 2 S0 4 (c)] T, K cal/Cmol-K) kcal/mol Log Kf Cp* S° -(G° - Hl 98 )/T TjO TjO 11 H 298 AHf° AGf° 298.15 31.523 48.020 48.020 -171.040 -147.787 108.329 300 31.606 48.215 48.022 .058 -171.040 -147.642 107.556 368.3 34.137 54.979 48.695 2.314 -170.967 -142.322 84.453 368.3 34.137 54.979 48.695 2.314 -171.063 -142.322 84.453 388.36 34.881 56.810 49.068 3.006 -171.024 -140.757 79.210 388.36 34.881 56.810 49.068 3.006 -171.437 -140.757 79.210 400 35.312 57.846 49.309 3.415 -171.427 -139.838 76.403 432.02 36.242 60.601 50.045 4.561 -171.404 -137.311 69.462 500 38.217 66.046 51.856 7.095 -171.392 -131.940 57.670 600 40.833 73.247 54.832 11.049 -171.075 -124.072 45.192 699 43.309 79.645 57.903 15.198 -170.547 -116.356 36.380 699 43.732 85.229 57.903 19.099 -166.646 -116.356 36.380 700 43.754 85.316 57.945 19.160 -166.622 -116.286 36.306 717.82 44.038 86.419 58.638 19.942 -166.494 -115.006 35.015 Phase changes : AH 0.096 kcal/mol. 368.3 K, orthrhombic-monoclinic transformation of S; 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 698.6 K, first-order transition of Ag 2 S0 4 (c); AH° = 3.901 kcal/mol. 717.824 K, boiling point of S to equilibrium of S n (n = 1 to 8). Sources: The enthalpy of formation and entropy at 298 K are from Parker (50) . The heat ca- pacity at 298 K is from Latimer (40). See text for high-temperature enthalpy values. [Formation: Ag 2 S0 4 (c,l) Silver sulfate 2Ag(c) + 0.5S 2 (g) + 2 2 (g) = Ag 2 S0 4 (c,l) T, K cal/(mol«K) kcal/mol Log Kf c P ° S° -(G° - H° 298 )/T H° - H 2 9 8 AHf° AGf° 298.15 31.523 48.020 48.020 -186.395 -157.301 115.303 300 31.606 48.215 48.022 .058 -186.392 -157.119 114.460 400 35.312 57.846 49.309 3.415 -186.078 -147.403 80.536 500 38.217 66.046 51.856 7.095 -185.520 -137.794 60.229 600 40.833 73.247 54.832 11.049 -184.770 -128.312 46.737 699 43.309 79.645 57.903 15.198 -183.876 -119.067 37.227 699 43.732 85.229 57.906 19.099 -179.975 -119.067 37.227 700 43.754 85.316 57.945 19.160 -179.947 -118.982 37.147 800 45.348 91.263 61.744 23.615 -178.859 -110.349 30.145 900 46.941 96.696 65.330 28.229 -177.683 -101.858 24.734 926 47.355 98.039 66.230 29.455 -177.362 -99.672 23.524 926 35.000 102.963 66.230 34.015 -172.802 -99.671 23.524 1,000 35.000 105.653 69.048 36.605 -172.807 -93.826 20.505 1,025 35.000 106.518 69.952 37.480 -172. R18 -91.852 19.584 Phase changes 698.6 K, first-order transition of Ag 2 S0 4 (c); AH° = 3.901 kcal/mol, 926 K., melting point of Ag 2 S0 4 (c); AH° = 4.56 kcal/mol. Sources: The enthalpy of formation and entropy at 298 K. are from Parker (50) . The heat ca- pacity at 298 K. is from Latimer (40). See text for high-temperature enthalpy values. 16 [Formation: Al 2 (S0 4 ) 3 (c) Aluminum sulfate 2Al(c) + 3S(c,l) + 6 2 (g) = Al 2 (S0 4 ) 3 (c)] T, K cal/(mol'K) kcal/mol Log Kf Cp 4 S° -(G° - H| 98 )/T a h 298 AHf° AGf° CO -9.614 -814.440 -814.440 CO 100 12.860 12.860 100.510 -8.765 -818.453 -793.673 1,734.549 200 45.650 35.790 62.385 -5.319 -821.246 -767.722 838.917 298.15 62.000 57.200 57.200 -822.620 -741.116 543.246 300 62.140 57.584 57.201 .115 -822.635 -740.609 539.527 368.3 71.093 71.351 58.558 4.711 -822.898 -721.899 428.370 368.3 71.093 71.351 58.558 4.711 -823.186 -721.899 428.370 388.36 73.722 75.192 59.320 6.164 -823.195 -716.380 403.138 388.36 73.722 75.192 59.320 6.164 -824.434 -716.380 403.138 400 75.248 77.392 59.814 7.031 -824.475 -713.141 389.637 432.02 78.156 83.299 61.339 9.487 -824.592 -704.226 356.249 500 84.331 95.221 65.145 15.038 -824.913 -685.243 299.516 600 90.414 111.174 71.512 23.797 -824.557 -657.329 239.429 700 94.191 125.421 78.215 33.044 -823.742 -629.516 196.541 717.82 94.570 127.794 79.417 34.726 -823.566 -624.573 190.157 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH°^ *■ 0.096 kcal/mol. 388.36 K, melting point of S; AH° - 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH ■ kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation is from Wagman (63) corrected for the sulfate ion. The entropy at 298 K and low-temperature heat capacities are from Shomate (58); see discussion in text. The high-temperature enthalpy values are from Shomate (59). [Formation: Al 2 (S0 4 ) 3 (c) Aluminum sulfate 2Al(c,l) + 1.5S 2 (g) + 6 2 (g) = Al 2 (S0 4 ) 3 (c)] T, K cal/(mo. L-K) kcal/mol Log Kf c P ° S° -(G° - H| 98 )/T( TjO TjO a H 298 AHf° AGf° CO -3.614 -860.394 -860.394 CO 100 21.870 12.860 100.510 -8.765 -865.015 -834.143 1,822.995 200 45.650 35.790 62.385 -5.319 -867.693 -802.106 876.490 298.15 62.000 57.200 57.200 -868.685 -769.657 564.167 300 62.140 57.584 57.201 .115 -868.691 -769.041 560.239 400 75.248 77.392 59.814 7.031 -868.428 -735.838 402.038 500 84.331 95.221 65.145 15.038 -867.295 -702.803 307.191 600 90.414 111.174 71.512 23.797 -865.641 -670.051 244.063 700 94.191 125.421 78.215 33.044 -863.717 -637.602 199.066 800 96.318 138.152 84.927 42.580 -861.714 -605.443 165.397 900 97.440 149.568 91.486 52.274 -859.744 -573.528 139.270 933.61 97.693 153.145 93.642 55.553 -859.100 -562.852 131.757 933.61 97,693 153.145 93.642 55.553 -864.260 -562.851 131.757 1,000 98.194 159.874 97.818 62.056 -862.954 -541.465 '118.335 1,100 99.214 169.276 103.892 71.922 -860.982 -509.408 101.209 Phase changes : 933.61 K, melting point of Al; AH° = 2.580 kcal/mol. Sources: The enthalpy of formation is from Wagman (63) corrected for the sulfte ion. The en- tropy at 298 K. and low-temperature heat capacities are from Shomate (58); see discussion in text. The high-temperature enthalpy values are from Shomate (59). 17 [Formation: Al 2 (S0 4 ) 3 -6H 2 0(c) Aluminum sulfate hexahydrate 2Al(c) + 3S(c,l) + 9 2 (g) + 6H 2 (g) = Al 2 (S0 4 ) 3 -6H 2 0(c) ] T, K cal/(mol«K) kcal/mol Log Kf c P u S° -CG° - H5 98 )/T ti "298 AHf u AGf° 00 -18.137 -1,251.744 -1,251.744 00 100 41.570 29.710 192.980 -16.327 -1,261.180 -1,211.238 2,647.125 200 84.140 72.090 121.925 -9.967 -1,267.011 -1,158.799 1,266.261 298.15 118.061 112.188 112.188 -1,269.770 -1,105.002 809.978 300 118.652 112.920 112.190 .219 -1,269.798 -1,103.979 804.238 350 133.954 132.376 113.693 6.539 -1,270.155 -1,076.306 672.067 368.3 139.085 139.334 114.796 9.037 -1,270.127 -1,066.171 632.660 368.3 139.085 139.334 114.796 9.037 -1,270.415 -1,066.172 632.660 388.36 144.710 146.871 116.256 11.890 -1,270.293 -1,055.046 593.721 388.36 144.710 146.871 116.256 11.890 -1,271:. 532 -1,055.047 593.721 400 147.974 151.193 117.210 13.593 -1,271.474 -1,048.560 572.899 432.02 156.131 162.909 120.162 18.468 -1,271.208 -1,030.725 521.415 450 160.712 169.369 122.000 21.316 -1,271.182 -1,020.715 495.721 500 172.166 186.906 127.620 29.643 -1,270.256 -992.929 434.003 550 182.338 203.803 133.783 38.511 -1,268.808 -965.259 383.554 Phase changes : AH 5 368.3 K, orthorhombic-monoclinic transformation of S; 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 0.096 kcal/mol. Sources: The enthalpy of formation at 298 K is from Wagman (63) . See text for entropy at 298 K. Low-temperature heat capacities are from Shomate (58) . High-temperature heat capacities are estimated. [Formation: BaS0 4 (c) Barium sulfate Ba(c) + S(c,l) + 2 2 (g) = BaS0 4 (c) T, K cal/(mol«K) kcal/mol Log Kf c P u S° -(G u - H3 98 )/T TjO TJ° H H ?98 AHf° AGf° 298.15 24.414 31.600 31.600 -352.200 -325.668 238.718 300 24.537 31.749 31.602 .044 -352.204 -325.503 237.126 368.3 27.167 37.063 32.125 1.818 -352.261 -319.417 189.540 368.3 27.167 37.063 32.125 1.818 -352.357 -319.418 189.541 388.36 27.939 38.524 32.419 2.371 -352.363 -317.623 178.740 388.36 27.939 38.524 32.419 2.371 -352.776 -317.623 178.740 400 28.387 39.356 32.608 2.699 -352.795 -316.569 172.963 432.02 29.025 41.567 33.192 3.618 -352.868 -313.667 158.675 500 30.380 45.929 34.633 5.648 -353.153 -307.474 134.395 582 31.270 50.618 36.562 8.180 -353.524 -299.955 112.636 582 31.270 50.618 36.562 8.180 -353.524 -299.955 112.636 600 31.465 51.573 36.998 8.745 -353.538 -298.298 108.654 700 32.120 56.476 39.437 11.927 -353.627 -298.084 90*255 717.82 32.196 57.284 39.870 12.500 -353.648 -287.440 87.514 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° =» 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 582 K, a-6 transition point of Ba; AH° = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation at 298 K is from Parker (49) after correction for the sul- fate ion. The entropy at 298 K is from Parker (49) ; see discussion in text. The low-temper- ature heat capacity values are from Latimer (39) , while the relative high-temperature enthalpy values are from Lashchenko (36). 18 [Formation: BaS0 4 (c) Barium sulfate Ba(c,l) + 0.5S 2 (g) + 2 2 (g) = BaS0 4 (c)] T, K cal/(mo. L»K) kcal/mol Log Kf Cp° S° -(G° - H| 98 )/T TjO tjO AHf° AGf° 298.15 24. 414 31.600 31.600 -367.555 -335.182 245.692 300 24.537 31.749 31.602 .044 -367.556 -334.980 244.030 400 28.387 39.356 32.608 2.699 -367.446 -324.135 177.097 500 30.380 45.929 34.633 5.648 -367.281 -313.327 136.953 582 31.270 50.618 36.562 8.180 -367.291 -304.481 114.336 582 31.270 50.618 36.562 8.180 -367.291 -304.481 114.336 600 31.465 51.573 36.998 8.745 -367.233 -302.539 110.198 700 32.120 56.476 39.437 11.927 -366.952 -291.779 91.096 768 32.409 59.469 41.080 14.123 -366.816 -284.485 80.955 800 32.545 60.795 41.842 15.162 -366.755 -281.056 76.780 900 32.836 64.646 44.166 18.432 -366.531 -270.357 65.651 1,000 33.043 68.117 46.391 21.726 -366.307 -259.684 56.753 1,002 33.046 68.183 46.434 21.792 -366.303 -259.470 56.593 1,002 33.046 68.183 46.434 21.792 -368.155 -259.471 56.593 1,100 33.194 71.273 48.511 25.038 -367.993 -248.846 49.441 1,200 33.308 74.167 60.530 28.364 -367.805 -238.023 43.349 1,300 33.394 76.836 52.452 31.699 -367.607 -227.215 38.198 Phase changes : 582 K, a-$ transition point of Ba; AH° = kcal/mol. 768 K, 6-y transition point of Ba; AH = kcal/mol. 1,002 K, melting point of Ba; AH° = 1.852 kcal/mol. Sources: The enthalpy of formation at 298 K is from Parker ( 49 ) after correction for the sul- fate ion. The entropy at 298 K is from Parker (49); see discussion in text. The low-temper- ature heat capacity values are from Latimer (39) , while the relative high-temperature enthalpy values are from Lashchenko (36). [Formation: BeS0 4 (a,B,Y) Beryllium sulfate Be(c) + S(c,l) + 2 2 (g) = BeS0 4 (a,e,Y)] T, K cal/(mol*K) kcal/mol Log Kf Cp° S° -(G° - H| 98 )/T TjO TjO H tl 298 AHf° AGf° OO -3.102 -284.510 -284.510 OO 100 7.008 4.453 32.603 -2.815 -285.785 -277.639 606.772 200 14.502 11.683 20.323 -1.728 -286.621 -268.885 293.820 298.15 20.482 18.635 18.635 -287.080 -260.453 190.915 300 20.581 18.762 18.635 .038 -287.085 -260.289 189.618 368.3 23.482 23.309 19.083 1.556 -287.206 -254.172 150.824 368.3 23.482 23.309 19.083 1.556 -287.302 -254.172 150.824 388.36 24.334 24.577 19.335 2.036 -287.320 -252.367 142.018 388.36 .24.334 24.577 19.335 2.036 -287.733 -252.367 142.018 400 24.828 25.303 19.498 2.322 -287.757 -251.307 137.306 432.02 25.783 27.252 20.001 3.132 -287.827 -248.387 125.652 500 27.810 31.180 21.258 4.961 -288.018 -242.163 105.848 600 30.310 36.470 23.360 7.866 -288.025 -232.983 84.863 700 32.980 41.340 25.584 11.029 -287.793 -223.828 69.881 717.82 33.483 42.175 25.986 11.621 -287.724 -222.200 67.651 Phase changes: 0.096 kcal/mol. 368.3 K, orthorhombic-monoclinic transformation of S; AH 388.36 K, melting point of S; AH = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° ■ kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation at 298 K is based on Navratil (44) after correction for the sulfate ion. Low-temperature heat capacity values, the entropy at 298 K, and the relative high-temperature enthalpy values are from JANAF (15). 19 [Formation: BeS0 4 (a,S,Y) Beryllium sulfate Be(c.l) + 0.5S 2 (g) + 2 2 (g) = BeS0 4 (a,S,Y)l T, K cal/(mol«K) kcal/mol Log Kf Cp° S 6 -(G° - H| 98 )/T TjO TjO H H 298 AHf° AGf° 00 -3.102 -299.828 -299.828 00 100 7.008 4.453 32.603 -2.815 -301.305 -291.129 636.254 200 14.502 11.683 20.323 -1.728 -302.103 -280.346 306.344 298.15 20.482 18.635 18.635 -302.435 -269.967 197.889 300 20.581 18.762 18.635 .038 -302.437 -269.766 196.522 400 24.828 25.303 19.498 2.322 -302.408 -258.872 141.439 500 27.810 31.180 21.258 4.961 -302.145 -248.017 108.407 600 30.310 36.470 23.360 7.866 -301.719 -237.224 86.408 700 32.980 41.340 25.584 11.029 -301.118 -226.524 70.723 800 35.800 45.927 27.843 14.467 -300.309 -215.920 58.986 863 37.650 48.709 29.265 16.780 -299.682 -209.295 53.002 863 37.650 49.017 29.265 17.046 -299.416 -209.295 53.002 900 38.730 50.620 30.110 18.459 -299.003 -205.439 49.887 908 38.970 50.964 30.292 18.770 -298.909 -204.608 49.247 908 38.970 56.110 30.292 23.443 -294.236 -204.608 49.247 1,000 41.690 60.004 32.844 27.160 -293.037 -195.582 42.744 1,100 43.759 64.080 35.501 31.437 -291.547 -185.909 36.936 1,200 45.222 67.953 38.045 35.890 -289.924 -176.380 32.123 1,300 46.258 71.616 40.488 40.466 -288.221 -166.982 28.072 1,400 46.984 75.072 42.836 45.130 -286.471 -157.720 24.621 1,500 47.480 78.331 45.094 49.855 -284.697 -148.596 21.650 1,527 47.567 79.179 45.690 51.138 -284.218 -146.144 20.916 1,527 47.567 79.179 45.690 51.138 -284.829 -146.144 20.916 1,560 47.673 80.198 46.410 52.710 -284.243 -143.162 20.056 1,560 47.673 80.198 46.410 52.710 -287.162 -143.164 20.056 1,600 47.802 81.407 47.269 54.620 -286.424 -139.478 19.052 1,700 47.970 84.310 49.363 59.410 -284.571 -130.360 16.759 1,800 48.000 87.053 51.381 64.209 -282.724 -121.345 14.733 1,900 48.000 89.649 53.328 69.009 -280.892 -112.414 12.930 2,000 48.000 92.111 55.207 73.809 -279.073 -103.597 11.320 Phase changes : 863 K, a-g transition point of BeS0 4 ; AH° = 0.266 kcal/mol. 908 K, 8-y transition point of BeS0 4 ; AH° = 4.673 kcal/mol. 1,527 K, a-6 transition point of Be; AH = 0.611 kcal/mol. 1,560 K, melting point of Be; AH° = 2.919 kcal/mol. Sources: The enthalpy of formation at 298 K is based on Navratil (44) after correction for the sulfate ion. Low-temperature heat capacity values, the entropy at 298 K, and the relative high-temperature enthalpy values are from JANAF (15). 20 [Formation: BeS0 4 'H 2 0(c) Beryllium sulfate monohydrate Be(c) + S(c,l) + 2.5 2 (g) = BeS0 4 -H 2 0(c) T, K cal/(mol«K) kcal/mol Log Kf Cp° S° -(G° - H5 98 )/T TjO Tjfl H u 298 AHf° AGf° 298.15 28.560 28.910 28.910 -361.150 -320.977 235.280 300 28.726 29.087 28.910 .503 -361.159 -320.728 233.647 350 33.227 33.853 29.276 1.602 -361.326 -313.974 196.052 368.3 34.874 35.588 29.547 2.225 -361.342 -311.498 184.841 368.3 34.874 35.588 29.547 2.225 -361.438 -311.498 184.841 388.36 36.679 37.485 29.907 2.943 -361.429 308.777 173.762 388.36 36.679 37.485 29.907 2.943 -361.842 -308.777 173.762 400 37.727 38.584 20.144 3.376 -361.841 -307.187 167.837 432.02 40.609 41.598 30.883 4.629 -361.808 -302.814 153.185 450 42.227 43.287 31.345 5.374 -361.829 -300.360 145.873 500 46.727 47.969 32.773 7.598 -361.584 -293.541 128.305 550 51.227 52.634 34.367 10.047 -361.126 -286.752 113.943 Phase changes: 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH = kcal/mol. Sources: The enthalpy of formation at 298 K is based on Broers The entropy and heat capacity value at 298 K are from Broers (_5) . ities are estimated. ( _5) ; see discussion in text. High-temperature heat capac- [ Formation: BeS0 4 «2H 2 0(c) Beryllium sulfate dihydrate Be(c,l) + S(c,l) + 3 2 (g) + 2H 2 (g) BeS0 4 «2H 2 0) T, K cal/(mol«K) kcal/mol Log Kf Cp° S° -(G° - H2 98 )/T U° - u°~~ u u 298 AHf° AGf° 00 -5.865 -428.770 -428.770 00 100 14.330 12.890 64.290 -5.140 -431.735 -415.484 908.027 200 26.280 26.250 42.040 -3.104 -433.606 -398.188 435.114 298.15 36.630 39.010 39.010 0.000 -434.780 -381.009 279.283 300 36.808 39.237 39.010 0.068 -434.794 -380.676 277.318 350 41.383 45.261 39.475 2.025 -435.075 -371.631 232.054 368.3 42.892 47.409 39.817 2.796 -435.135 -368.312 218.554 368.3 42.892 47.409 39.817 2.796 -435.231 -368.312 218.554 388.36 44.546 49.731 40.269 3.675 -435.272 -364.665 205.213 388.36 44.546 49.731 40.269 3.675 -435.686 -364.665 205.213 400 45.506 51.061 40.563 4.199 -435.717 -362.536 198.078 432.02 47.856 54.659 41.475 5.696 -435.779 -356.676 180.432 450 49.175 56.637 42.041 6.568 -435.864 -353.384 171.625 500 52.392 61.988 43.770 9.109 -435.836 -344.219 150.456 550 55.155 67.115 45.662 11.799 -435.674 -335.061 133.139 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH = 0.096 kcal/mol. 388.36 K, melting point of S; AH = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n - 1 to 8). Sources: The enthalpy of formation at 298 K. is from Navratil (44) . The entropy at 298 K and low-temperature heat capacity values are from Gardner (23). High-temperature heat capacities are estimated. 21 [Formation: BeS0 4 «4H 2 0(c) Beryllium sulfate tetrahydrate Be(c,l) + S(c,l) + 4 2 (g) + 4H 2 (g) = BeS0 4 -4H 2 0)] T, K cal/(mol«K) kcal/mol Log Kf Cp° S* -(G° - H 298 )/T TjO TjO H hl 298 AHf° AGf° 00 -8.306 -568.688 -568.688 OO 100 20.880 18.850 91.140 -7.229 -573.429 -548.825 1,199.440 200 36.720 38.180 59.840 -4.332 -576.423 -522.688 571.159 298.15 51.770 55.680 55.680 0.000 -578.380 -496.359 363.836 300 52.049 56.001 55.681 0.096 -578.405 -495.851 361.223 350 59.503 64.586 56.343 2.885 -578.899 -482.049 301.001 368.3 62.184 67.687 56.830 3.998 -579.001 -476.982 283.038 368.3 62.184 67.687 56.830 3.998 -579.097 -476.982 283.038 388.36 65.124 71.063 57.477 5.276 -579.162 -471.417 265.287 388.36 65.124 71.063 57.477 5.276 -579.575 -471.417 265.287 400 66.829 73.011 57.901 6.044 -579.609 -468.175 255.795 432.02 71.437 78.333 59.218 8.258 -579.632 -459.253 232.323 450 74.025 81.299 60.041 9.566 -579.665 -454.245 220.609 500 81.091 89.465 62.575 13.445 -579.366 -440.321 192.462 550 88.028 97.520 65.387 17.673 -578.740 -426.440 169.450 Phase changes 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. Sources: The enthalpy of formation at 298 K is from Navratil (44). Th entropy at 298 K and low-temperature heat capacity values are from Gardner (23) . High-temperature heat capacities are estimated. CaS0 4 (i,c) Calcium sulfate (insoluble anhydrite) [Formation: Ca(c) + S(c,l) + 2 2 (g) = CaS0 4 (i,c) T, K cal/(mo. L-K) kcal/mol Log Kf Cp° S° -(G° - Hl 98 )/T H - H 298 AHf° AGf° oa -4.105 -340.370 -340.370 CO 100 11.007 6.707 43.307 -3.660 -341.711 -333.422 728.685 200 19.067 17.073 27.663 -2.118 -342.496 -324.790 354.909 298.15 23.878 25.620 25.620 -342.840 -316.009 231.638 300 23.965 25.771 25.621 .045 -342.842 -315.841 230.087 368.2 25.873 30.956 26.140 1.774 -342.881 -309.689 183.768 368.3 25.873 30.956 26.140 1.774 -342.977 -309.689 183.768 388.36 26.434 32.344 26.425 2.298 -342.983 -307.876 173.255 388.36 26.434 32.344 26.425 2.298 -343.396 -307.876 173.255 400 26.759 33.129 26.609 2.608 -343.415 -306.811 167.632 432.02 27.483 35.218 27.171 3.476 -343.475 -303.879 153.724 500 20.019 39.343 28.549 5.397 -343.668 -297.630 130.092 600 31.279 44.833 30.813 8.412 -343.704 -288.412 105.053 700 33.538 49.825 33.178 11.653 -343.551 -279.212 87.173 717.82 33.941 50.673 33.602 12.254 -343.505 -277.572 84.509 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation at 298 K is from Parker (49^) corrected for the heat of formation of the sulfate ion. See text for discussion of entropy values at 298 K. Low-temper- ature heat capacities from Kelley (31) . The high-temperature enthalpies are from Lashchenko (37). 22 CaS0 4 (i,c) Calcium sulfate (insoluble anhydrite) formation: Ca(c,l) + 0.5S 2 (g) + 2 2 (g) = CaS0 4 (i,c) T, K cal/(mol«K) kcal/mol Log Kf Cp° S° -(G° - H| 98 )/T a u 298 AHf° AGf° OS -4.105 -355.688 -355.688 OO 100 11.007 6.707 43.307 -3.660 -357.232 -346.912 758.166 200 19.067 17.073 27.663 -2.118 -357.979 -336.251 367.434 298.15 23.878 25.620 25.620 -358.195 -325.523 238.612 300 23.965 25.771 25.621 .045 -358.194 -325.319 236.991 400 26.759 33.129 26.609 2.608 -358.066 -314.377 171.765 500 29.019 39.343 28.549 5.397 -357.796 -303.483 132.651 600 31.279 44.833 30.813 8.412 -357.398 -292.653 106.597 700 33.538 49.825 33.178 11.653 -356.876 -281.907 88.014 720 33.990 50.776 33.654 12.328 -356.758 -279.765 84.919 720 33.99G 50.776 33.654 12.328 -356.978 -279.765 84.919 800 35.798 54.451 35.551 15.120 -356.406 -271.212 74.091 900 38.058 58.797 37.895 18.812 -355.592 -260.596 63.280 1,000 40.318 62.924 40.193 22.731 -354.719 -250.105 54.660 1,100 42.577 66.873 42.440 26.876 -353.727 -239.687 47.621 1,112 42.848 67.336 42.706 27.389 -353.600 -238.452 46.864 1,112 42.848 67.336 42.706 27.389 -355.641 -238.452 46.864 1,200 44.837 70.674 44.635 31.247 -354.288 -229.225 41.747 1,300 47.097 74.352 46.780 35.843 -352.559 -218.874 36.796 1,400 49.356 77.925 48.878 40.666 -350.623 -208.660 32.573 Phase changes : 720 K, a-e transition point of Ca; AH° = 0.220 kcal/mol. 1,112 K, melting point of Ca; AH° = 2.040 kcal/mol. Sources: The enthalpy of formation at 298 K is from Parker ( 49 ) corrected for the heat of formation of the sulfate ion. See text for discussion of entropy values at 298 K. Low-temper- ature heat capacities are from Kelley (31) . The high-temperature enthalpies are from Lashchenko (37). CaS0 4 (8,c) Calcium sulfate (g-soluble anhydrite) [Formation: Ca(c) + S(c,l) + 2 2 (g) = CaS0 4 (B,c)] T, K cal/(mol«K) kcal/mol Log Kf Cp° S° -(G° - H| 98 )/T TjO TjO H u 298 AHf° AGf° 00 -4.146 -337.231 -337.231 OO 100 11.576 6.579 43.479 -3.690 -338.561 -330.260 721.772 200 19.149 17.138 27.758 -2.124 -339.322 -321.629 351.455 298.15 23.690 25.720 25.720 -339.660 -312.859 229.329 300 23.754 25.871 25.721 .045 -339.662 -312.691 227.793 368.3 25.806 31.059 26.240 1.775 -339.700 -306.546 181.903 368.3 25.806 31.059 26.240 1.775 -339.796 -306.546 181.903 388.36 26.409 32.444 26.525 2.299 -339.803 -304.734 171.487 388.36" 26.409 32.444 26.525 2.299 -340.216 -304.735 171.487 400 26.759 33.229 26.709 2.608 -340.235 -303.671 165.916 432.02 27.483 35.318 27.271 3.476 -340.296 -300.742 152.137 500 20.019 39.443 28.649 5.397 -340.488 -294.500 128.724 600 31.279 44.933 30.913 8.412 -340.524 -285.292 103.916 700 33.538 49.925 33.278 11.653 -340.371 -276.102 86.202 717.82 33.941 50.773 33.702 12.254 -340.325 -274.464 83.563 Phase ch ange : 368 .3 K, ortl "lorhombic-monoclii lie transforma tion of S; AH' ' = 0.096 kca 1/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mo 717.824 K, boiling point of S to equilibrium mixture of S n Sources: The enthalpy of formation at 298 K is from Parker (49) correc formation of the sulfate ion. See text for discussion of entropy values at ature heat capacities are from Kelley (31) . The high-temperature enthalpies (37). 1. (n = 1 to 8). ted for the heat of 298 K. Low-temper- are from Lashchenko 23 CaS0 4 (p\c) Calcium sulfate (S-soluble anhydrite) [Formation: Ca(c,l) + 0.5S 2 (g) + 2 2 (g) = CaS0 4 (p\c); T, K cal/(mol«K) kcal/mol Log Kf Cp° S° -(G° - H| 98 )/T H ti 298 AHf° AGf° 00 -4.146 -352.549 -352.549 OO 100 11.576 6.579 43.479 -3.690 -354.082 -343.749 751.254 200 19.149 17.138 27.758 -2.124 -354.805 -333.090 363.979 298.15 23.690 25.720 25.720 -355.015 -322.373 236.302 300 23.754 25.871 25.721 .045 -355.014 -322.169 234.697 400 26.759 33.229 26.709 2.608 -354.886 -311.237 170.050 500 29.019 39.443 28.649 5.397 -354.616 -300.353 131.283 600 31.279 44.933 30.913 8.412 -354.219 -289.533 105.461 700 33.538 49.925 33.278 11.653 -353.696 -278.797 87.043 720 33.990 50.876 33.754 12.328 -353.578 -276.657 83.976 720 33.990 50.876 33.754 12.328 -353.798 -276.657 83.976 800 35.798 54.551 35.651 15.120 -353.227 -268.112 73.244 900 38.058 58.897 37.995 18.812 -352.413 -257.506 62.530 1,000 40.318 63.024 40.293 22.731 -351.539 -247.025 53.986 1,100 42.577 66.973 42.540 26.876 -350.547 -236.617 47.011 1,112 42.848 67.436 42.806 27.389 -350.421 -235.384 46.261 1,112 42.848 67.436 42.806 27.389 -352.461 -235.384 46.261 1,200 44.837 70.774 44.735 31.247 -351.108 -226.165 41.190 1,300 47.097 74.452 46.880 35.843 -349.379 -215.824 36.283 1,400 49.356 78.025 48.978 40.666 -347.443 -205.620 32.098 Phase changes : 720 K, a-3 transition point of Ca; AH° = 0.220 kcal/mol. 1,112 K, melting point of Ca; AH° = 2.040 kcal/mol. Source- The enthalpy of formation at 298 K is from Parker ( 49 ) corrected for the heat of formation )f the sulfate ion. See text for discussion of entropy values at 298 K. Low-temper- ature heac capacities are from Kelley ( 31 ) . The high-temperature enthalpies are from Lashchenko (37). CaS0 4 (a,c) Calcium sulfate (a-soluble anhydrite) [Formation: Ca(c) + S(c ,1) + 2 2 (g) = CaS0 4 (a,c)] T, K cal/(mol«K) kcal/mol Log Kf Cp° S* -(G° - H| 98 )/T nO TlO H "298 AHf° AGf° OO -4.156 -338.301 -338.301 OO 100 11.350 6.920 43.860 -3.694 -339.625 -331.358 724.172 200 19.149 17.450 28.095 -2.129 -340.387 -322.756 352.687 298.15 23.940 26.050 26.050 -340.720 -314.017 230.178 300 24.010 26.201 26.051 .045 -340.722 -313.850 228.637 368.3 25.888 31.386 26.570 1.774 -340.761 -307.728 182.604 368.3 25.888 31.386 26.570 1.774 -340.857 -307.728 182.604 388.36 26.439 32.773 26.855 2.298 -340.863 -305.923 172.156 388.36 26.439 32.773 26.855 2.298 -341.276 -305.923 172.156 400 26.759 33.559 27.039 2.608 -341.295 -304.863 166.567 432.02 27.483 35.647 27.601 3.476 -341.355 -301.945 152.746 500 29.019 39.773 28.979 5.397 -341.548 -295.725 129.260 600 31.279 45.263 31.243 8.412 -341.584 -286.550 104.375 700 33.538 50.255 33.608 11.653 -341.431 -277.393 86.605 717.82 33.941 51.103 34.032 12.254 -341.385 -275.761 83.958 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation at 298 K is from Parker (49) corrected for the heat of formation of the sulfate ion. See text for discussion of entropy values at 298 K. Low-temper- ature heat capacities are from Kelley (31). The high-temperature enthalpies are from Lashchenko (37). 24 CaS0 4 (a,c) Calcium sulfate (a-soluble anhydrite) [Formation: Ca(c,l) + 0.5S 2 (g) + 2 2 (g) = CaS0 4 (a,c)] T, K cal/(mo] ■•K) kcal/mol Log Kf Cp° S° -(G° - Hl 98 )/T TjO TjO h "298 AHf° AGf° . OO -4.156 -353.619 -353.619 OO 100 11.350 6.920 43.860 -3.694 -355.146 -344.848 753.654 200 19.149 17.450 28.095 -2.129 -355.870 -334.218 365.211 298.15 23.940 26.050 26.050 -356.075 -323.531 237.152 300 24.010 26.201 26.051 .045 -356.074 -323.328 235.541 400 26.759 33.559 27.039 2.608 -355.946 -312.429 170.701 500 29.019 39.773 28.979 5.397 -355.676 -301.578 131.818 600 31.279 45.263 31.243 8.412 -355.279 -290.791 105.919 700 33.538 50.255 33.608 11.653 -354.756 -280.088 87.446 720 33.990 51.206 34.084 12.328 -354.638 -277.954 84.370 720 33.990 51.206 34.084 12.328 -354.858 -277.954 84.370 800 35.798 54.881 35.981 15.120 -354.286 -269.436 73.606 900 38.058 59.227 38.325 18.812 -353.473 -258.863 62.860 1,000 40.318 63.354 40.623 22.731 -352.599 -248.415 54.290 1,100 42.577 67.303 42.870 26.876 -351.607 -238.040 47.294 1,112 42.848 67.766 43.136 27.389 -351.480 -236.810 46.542 1,112 42.848 67.766 43.136 27.389 -353.521 -236.810 46.542 1,200 44.837 71.104 45.065 31.247 -352.168 -227.621 41.455 1,300 47.097 74.782 47.210 35.843 -350.439 -217.313 36.533 1,400 49.356 78.355 49.308 40.666 -348.503 -207.142 32.336 Phase changes 720 K, ci-B transition point of Ca; AH° = 0.220 kcal/mol. 1,112 K, melting point of Ca; AH° = 2.040 kcal/mol. Sources: The enthalpy of formation at 298 K is from Parker (49) corrected for the heat of formation of the sulfate ion. See text for discussion of entropy values at 298 K. Low-temper- ature heat capacities are from Kelley ( 31 ) . The high-temperature enthalpies are from Lashchenko (37). CaS0 4 '2H 2 0(c) Calcium sulfate dihydrite [Formation: Ca(c) + S(c,l) + 2H 2 (g) + 3 2 (g) = CaS0 4 -2H 2 0(c)] T, K cal/(mol«K) kcal/mol Log Kf c P a S° -(G° - Hl 98 )/T TjO TjO H "298 AHf° AGf° 00 -7.419 -478.221 -487.221 OO 100 19.150 12.410 78.530 -6.612 -481.328 -464.661 1,015.502 200 34.310 30.630 50.120 -3.898 -482.925 -447.281 488.760 298.15 44.102 46.400 46.400 -483.500 -429.645 314.934 300 44.236 46.673 46.400 .082 -483.504 -429.309 312.748 350 47.157 53.729 46.952 2.372 -483.547 -420.273 262.427 368.3 47.742 56.147 47.349 3.240 -483.543 -416.964 247.424 368.3 47.742 56.147 47.349 3.240 -483.639 -416.964 247.424 388.36 48.384 58.711 47.871 4.210 -483.623 -413.333 232.600 388.36 48.384 58.711 47.871 4.210 -484.036 -413.333 232.600 400 48.756 60.145 48.208 4.775 -484.045 -411.214 224.674 432.02 48.933 63.919 49.231 6.345 -484.082 -405.382 205.071 450 49.033 65.916 49.858 7.226 -484.182 -402.106 195.287 500 47.988 71.040 51.726 9.657 -484.334 -392.978 171.768 550 45.621 75.513 53.691 12.002 -484.584 -383.829 152.518 Phase changes : AH 368.3 K, orthorhombic-monoclinic transformation of S; 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 0.096 kcal/mol. Sources: The enthalpy of formation at 298 K is from Parker ( 49 ) corrected for the heat of formation of the sulfate ion. The entropy at 298 K is from Parker (49) . Low-temperature heat capacity values are from Latimer (39), while the high-temperature values are estimated. 25 CaS0 4 'l/2H 2 0(a,c) Calcium sulfate hemihydrite (a-soluble hemlhydrate) [Formation: Ca(c) + S(c,l) + 0.5H 2 (g) + 2.25 2 (g) = CaS0 4 «l/2H 2 0(a,c)] T, K cal/(mol-K) kcal/mol Log Kf Cp a S° -(6° - H5 98 )/T TjO TjO H H 298 AHf° AGf° 298.15 28.543 31.200 31.200 -376.930 -343.458 251.758 300 28.632 31.377 31.200 .053 -376.934 -343.249 250.053 350 30.745 35.957 31.557 1.540 -376.997 -337.629 210.822 368.3 31.295 37.538 31.815 2.108 -377.004 -335.570 199.126 368.3 31.295 37.538 31.815 2.108 -377.100 -335.570 199.126 388.36 31.899 39.220 32.155 2.744 -377.101 -333.308 187.567 388.36 31.899 39.220 32.155 2.744 -377.514 -333.308 187.567 400 32.249 40.167 32.375 3.117 -377.530 -331.983 181.385 432.02 32.822 42.678 33.044 4.162 -377.584 -328.335 166.095 450 33.144 44.023 33.456 4.755 -377.684 -326.284 158.463 500 33.429 47.536 34.694 6.421 -377.801 -320.567 140.118 550 33.105 50.711 36.007 8.087 -377.924 -314.835 125.102 Ptfese changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° =» kcal/mol. Sources: The enthalpy of formation at 298 K is from Parker (49) corrected for the heat of formation of the sulfate ion. The entropy at 298 K is from Parker (49) . The heat capacity at 298 K is from Kelley (31). High-temperature heat capacities are estimated. CaS0 4 .l/2H 2 0(8,c) Calcium sulfate hemihydrite ( 8-soluble hemihydrate) [Formation: Ca(c) + S(c,l) + 0.5H 2 (g) + 2.25 2 (g) = CaS0 4 «l/2H 2 0(S,c)] T, K cal/(mol«K) kcal/mol Log Kf Cp" S° -(G° - H5 98 )/T TjO TJO tl H 298 AHf° AGf° 298.15 29.690 32.100 32.100 -376.430 -343.226 251.588 300 29.802 32.284 32.101 .055 -376.432 -343.019 249.886 350 32.995 37.119 32.476 1.625 -376.412 -337.451 210.711 368.3 34.137 38.830 32.750 2.239 -376.373 -335.415 199.033 368.3 34.137 38.830 32.750 2.239 -376.469 -335.415 199.033 388.36 35.388 40.673 33.111 2.937 -376.408 -333.179 187.494 388.36 35.388 40.673 33.111 2.937 -376.821 -333.179 187.494 400 36.114 41.729 33.347 3.353 -376.794 -331.872 181.324 432.02 38.064 44.585 34.074 4.541 -376.705 -328.280 166.068 450 39.159 46.159 34.526 5.235 -376.704 -326.265 158.454 500 42.129 50.439 35.903 7.268 -376.453 -320.672 140.164 550 45.025 54.591 37.415 9.447 -376.064 -315.109 125.211 Phase changes AH 368.3 K, orthorhombic-monoclinic transformation of S; 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 0.096 kcal/mol, Sources: The enthalpy of formation at 298 K is from Parker (49) corrected for the heat of formation of the sulfate ion. The entropy at 298 K is from Parker (49) . Low-temperature heat capacity values are from Latimer (39), while the high-temperature valkues are estimated. 26 [Formation: CdS0 4 (c) Cadmium sulfate Cd(c,l) + S(c,l) + 2 2 (g) = CdS0 4 (c) T, K. cal/(mol«K) kcal/mol Log Kf Cp° S" -(G° - H| 98 )/T H "298 AHf° AGf° 298.15 23.806 29.408 29.408 -223.100 -196.671 144.162 300 23.875 29.555 29.408 .044 -223.103 -196.506 143.152 368.3 25.922 34.652 29.917 1.744 -223.183 -190.442 113.007 368.3 25.922 34.652 29.917 1.744 -223.279 -190.442 113.007 388.36 26.523 36.044 30.198 2.270 -223.288 -188.653 106.163 388.36 26.523 36.044 30.198 2.270 -223.701 -188.653 106.163 400 26.872 36.832 30.380 2.581 -223.721 -187.602 102.500 432.02 27.718 38.934 30.937 3.455 -223.783 -184.709 93.439 500 29.513 43.117 32.311 5.403 -223.962 -178.541 78.039 594.26 31.806 48.409 34.452 8.294 -223.953 -169.976 62.511 594.26 31.806 48.409 34.452 8.294 -225.433 -169.976 62.511 600 31.946 48.715 34.587 8.477 -225.428 -169.435 61.716 700 34.289 53.816 36.975 11.789 -225.182 -160.123 49.992 717.82 34.701 54.683 37.403 12.404 -225.112 -158.467 48.247 Phase changes 368.3 K, orthorhombic-monoclinic transformation of S; AH° «* 0.O96 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 594.26 K, melting point of Cd; AH° = 1.480 kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation at 298 K is based on Adami (1); see text. The entropy and heat capacity at 298 K are from Papadopoulos (47). High-temperature enthalpies were estimated. [Formation: CdS0 4 (c) Cadmium sulfate Cd(c,l) + 0.5S 2 (g) + 2 2 (g) = CdS0 4 (c)] T, K cal/(mol«K) kcal/mol Log Kf c P 6 S* -(G° - H| 98 )/T tjb tjO 11 H 298 AHf° AGf° 298.15 23.806 29.408 29.408 -238.455 -206.185 151.136 300 23.875 29.555 29.408 .044 -238.455 -205.983 150.056 400 26.872 36.832 30.380 2.581 -238.372 -195.168 106.633 500 29.513 43.117 32.311 5.403 -238.090 -184.394 80.598 594.26 31.806 48.409 34.452 8.294 -237.670 -174.307 64.104 594.26 31.806 48.409 34.452 8.294 -239.150 -174.307 64.104 600 31.946 48.715 34.587 8.477 -239.122 -173.676 63.261 700 34.289 53.816 36.975 11.789 -238.507 -162.818 50.833 800 36.600 58.546 39.380 15.333 -237.705 -152.059 41.540 Phase changes : 594.26 K, melting point of Cd; AH° = 1.480 kcal/mol. Sources: The enthalpy of formation at 298 K is based on Adami ( 1_) ; see text. The entropy and heat capacity at 298 K are from Papadopoulos (47). High-temperature enthalpies were estimated. 27 [Formation: CdS0 4 'H 2 0(c) Cadmium sulfate monohydrate Cd(c) + S(c,l) + H 2 (g) + 2.5 2 (g) = CdS0 4 -H 2 0(c)] T, K cal/(mo] •K) kcal/mol Log Kf Cp° S° -(G° - Hl 98 )/T TjO TTO " "298 AHf° AGf° 298.15 32.167 36.814 36.814 -296.340 -255.509 187.291 300 32.284 37.013 36.813 .060 -296.346 -255.254 185.950 350 - 35.284 42.220 37.220 1.750 -296.477 -248.397 155.104 368.3 36.259 44.043 37.514 2.405 -296.497 -245.882 145.905 368.3 36.259 44.043 37.514 2.405 -296.593 -245.882 145.905 388.36 37.329 45.997 37.902 3.144 -296.600 -243.119 136.814 388.36 37.329 45.997 37.902 3.144 -297.013 -243.119 136.814 400 37.949 47.109 38.154 3.582 -297.029 -241.504 131.950 432.02 39.440 50.091 38.928 4.822 -297.063 -237.058 119.921 450 40.278 51.716 39.407 5.539 -297.141 -234.559 113.916 500 42.273 56.066 40.856 7.605 -297.133 -227.603 99.484 550 43.933 60.176 42.429 9.761 -297.039 -220.655 87.679 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. Sources: The enthalpy of formation at 298 K is from Wagman ( 63 ) after correction for the heat of formation of the sulfate ion. The entropy and heat capacity at 298 K are from Papadopoulos (47). High-temperature enthalpies were estimated. [Formation: CdS0 4 .8/3H 2 0(c) Cadmium sulfate 8/3 hydrate Cd(c) + S(c,l) + 2.667H 2 (g) + 3.3333 2 (g) = CdS0 4 «8/3H 2 0(c) T, K cal/(mol«K) kcal/mol Log Kf c P 4 S a -(6° - Hi 98 )/T TjO IjO H "298 AHf° AGf° 298.15 50.985 54.883 54.883 , -413.410 -350.281 256.760 300 51.209 55.199 54.882 .095 -413.414 -349.888 254.890 350 57.141 63.542 55.531 2.804 -413.396 -339.300 211.866 368.3 59.214 66.507 56.003 3.869 -413.327 -335.428 199.041 368.3 59.214 66.507 56.003 3.869 -413.423 -335.428 199.041 388.36 61.486 69.710 56.627 5.081 -413.309 -331.181 186.370 388.36 61.486 69.710 56.627 5.081 -413.722 -331.181 186.370 400 62.805 71.545 57.035 5.804 -413.658 -328.709 179.596 432.02 66.261 76.515 58.295 7.871 -413.431 -321.917 162.849 450 68.201 79.256 59.078 9.080 -413.336 -318.111 154.494 500 73.330 86.710 61.470 12.620 -412.743 -307.559 134.432 550 78.191 93.929 64.094 16.409 -411.912 -297.078 118.047 Phase changes: 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. Sources: The enthalpy of formation at 298 K is from Wagman (63) after correction for the heat of formation of the sulfate ion. The entropy and heat capacity at 298 K are from Papadopoulos (47). High-temperature enthalpies were estimated. 28 Formation: 2Cd0-CdS0 4 (c) Cadmium oxysulfate 3Cd(c,l) + S(c,l) + 3 2 (g) = 2Cd0«CdS0 4 (c)] T, K cal/(mo; ■•K) kcal/mol Log Kf Cp° S° -(G° - H°29 8 )/T U° -I u°" H u 298 AHf° AGf° 298.15 46.126 58.929 58.929 -345.690 -306.070 224.352 300 46.341 59.215 58.928 .086 -345.686 -305.820 222.787 368.3 51.574 69.256 59.929 3.435 -345.461 -296.769 176.101 368.3 51.574 69.256 59.929 3.435 -345.557 -296.769 176.101 388.36 52.955 72.034 60.483 4.486 -345.443 -294.114 165.511 388.36 52.955 72.034 60.483 4.486 -345.856 -294.114 165.511 400 53.756 73.610 60.843 5.107 -345.800 -292.564 159.848 432.02 55.612 77.825 61.945 6.861 -345.632 -288.309 145.848 500 59.053 86.211 64.683 10.764 -345.265 -279.310 122.085 594.26 62.373 96.711 68.946 16.499 -344.422 -266.947 98.173 594.26 62.373 96.711 68.946 16.499 -348.862 -266.948 98.174 600 62.551 97.311 69.214 16.858 -348.812 -266.143 96.941 700 64.696 107.129 73.945 23.229 -347.705 -252.459 78.820 717.82 64.955 108.759 74.789 24.384 -347.489 -250.037 76.126 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° =» 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° » kcal/mol. 594.26 K, melting point of Cd; AH° - 1.480 kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation at 298 K is from Ko (33) . The entropy at 298 K are from Beyer (4), as are the high-temperature enthalpy values. and heat capacity [Formation: 2CdO«CdS0 4 (c) Cadmium oxysulfate 3Cd(c,l,g) + 0.5S 2 (g) + 3 2 (g) = 2CdO-CdS0 4 (c)] T, K cal/(mol«K) kcal/mol Log Kf c P ° S 6 -(G° - Hi 98 )/T TTfO TjO 11 "298 AHf° AGf° 298.15 46.126 58.929 58.929 -361.045 -315.583 231.326 300 46.341 59.215 58.928 .086 -361.038 -315.297 229.691 400 53.756 73.610 60.843 5.107 -360.451 -300.130 163.981 500 59.053 86.211 64.683 10.764 -359.392 -285.164 124.643 594.26 62.373 96.711 68.946 16.499 -358.140 -271.279 99.766 594.26 62.373 96.711 68.946 16.499 -362.580 -271.289 99.766 600 62.551 97.-311 69.214 16.858 -362.507 -270.384 98.486 700 64.696 107.129 73.945 23.229 -361.030 -255.155 79.662 800 66.012 115.859 78.648 29.769 -359.449 -240.134 65.601 900 67.098 123.696 83.225 36.424 -357.806 -225.307 54.711 1,000 68.630 130.838 87.634 43.204 -356.081 -210.670 46.041 1,040 69.723 133.551 89.348 45.971 -355.347 -204.895 43.057 1,040 69.723 133.551 89.348 45.971 -426.774 -204.895 43.057 1,100 71.362 137.495 91.868 50.190 -425.230 -192.136 38.173 Phase changes: 594.26 K, melting point of Cd; AH 1,040 K, boiling point of Cd; AH° =» 1.480 kcal/mol. 23.809 kcal/mol. Sources: The enthalpy of formation at 298 K is from Ko (33) . The entropy and heat capacity at 298 K are from Beyer (4), as are the high-temperature enthalpy values. 29 Cs 2 SO< >(c,l) Cesium sulfate [Formation: 2Cs(c,l) + S(c,l) + 2 2 (g) = Cs 2 S0 4 (c,l)] T, K cal/(moj L-K) kcal/mol Log Kf c P u S° -(G° - H| 98 )/T h dogs AHf u AGf° -6.628 -342.706 -342.706 100 21.340 21.970 75.900 -5.393 -344.049 -335.041 732.222 200 27.430 38.760 53.430 -2.934 -344.657 -325.770 355.980 298.15 32.619 50.640 50.640 -344.970 -316.416 231.936 300 32.697 50.842 50.642 .060 -344.974 -316.238 230.376 301.55 32.750 51.011 50.643 .111 -344.977 -316.089 229.084 301.55 32.750 51.011 50.643 .111 -345.977 -316.089 229.084 368.3 35.014 57.806 51.338 2.382 -346.046 -309.465 183.635 368.3 35.014 57.806 51.338 2.382 -346.142 -309.465 183.635 388.36 35.695 59.681 51.721 3.091 -346.143 -307.467 173.025 388.36 35.695 59.681 51.721 3.091 -346.556 -307.467 173.025 400 36.090 60.741 51.969 3.509 -346.569 -306.295 167.350 432/02 37.053 63.557 52.724 4.680 -346.606 -303.072 153.315 500 39.097 69.114 54.580 7.267 -346.708 -296.207 129.470 600 42.455 76.532 57.630 11.341 -346.485 -286.119 104.217 700 46.388 83.363 60.823 15.778 -345.884 -276.099 86.201 717.82 47.203 84.539 61.397 16.612 -345.732 -274.324 83.520 Phase ch anges : 30 1.55 K, m« siting point of & s; AH° - 0.500 kcal/mol. 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation at 298 K is from Wagman (6_5) after correction for the heat of formation of the sulfate ion. The low-temperature heat capacities are from Paukov (51) , while the high-temperature enthalpy values are from Shmidt (56) and Denielou (12); see text. 30 [Formation: Cs 2 S0 4 (c,l) Cesium sulfate 2Cs(c,l,g) + 0.5S 2 (g) + 2 2 (g) = Cs 2 S0 4 (c,l)] T, K cal/(moJ .•K) kcal/mol Log Kf ^F S° CG* • ii298)/T H" - H298 AHf° AGf° 00 -6.628 -358.024 -358.024 00 100 21.340 21.970 75.900 -5.393 -359.570 -348.531 761.704 200 27.430 38.760 53.430 -2.934 -360.139 -337.231 368.504 299.15 32.619 50.640 50.640 -360.325 -325.930 238.910 300 32.697 50.842 50.642 .060 -360.326 -325.715 237.280 301.55 32.750 51.011 50.643 .111 -360.327 -325.536 235.931 301.55 32.750 51.011 50.643 .111 -361.327 -325.536 235.931 400 36.090 60.741 51.969 3.509 -361.220 -313.861 171.483 500 39.097 69.114 54.580 7.267 -360.836 -302.060 132.029 600 42.455 76.532 57.630 11.341 -360.180 -290.360 105.762 700 46.388 83.363 60.823 15.778 -359.209 -278.794 87.042 800 50.959 89.849 64.049 20.640 -357.859 -267.397 73.049 900 56.175 96.146 67.267 25.991 -356.053 -256.192 62.211 952 59.208 99.380 68.932 28.987 -354.915 -250.478 57.501 952 59.208 99.380 68.932 28.987 -387.311 -250.478 57.501 997 61.832 103.175 70.370 31.710 -385.981 -244.040 53.495 997 46.293 102.248 70.370 31.782 -385.909 -244.041 53.495 1,000 46.405 102.387 70.466 31.921 -385.863 -243.613 53.241 1,100 50.109 106.984 73.578 36.747 -384.156 -229.467 45.590 1,200 53.813 111.502 76.549 41.943 -382.100 -215.490 39.246 1.278 56.702 114.981 78.789 46.253 -380.253 -204.718 35.008 1,278 49.393 121.609 78.790 54.723 -371.783 -204.719 35.008 1,300 49.393 122.452 79.522 55.809 -371.394 -201.847 33.933 1,400 49.393 126.112 82.720 60.749 -369.637 -188.870 29.484 1,500 49.393 129.520 85.728 65.688 -367.894 -176.020 25.646 1,600 49.393 132.708 88.566 70.627 -366.172 -163.286 22.303 1,700 49.393 135.702 91.251 75.567 -364.466 -150.656 19.368 1,800 49.393 138.526 93.800 80.506 -362.779 -138.127 16.771 1,900 49.393 141.196 96.225 85.445 -361.111 -125.694 14.458 2,000 49.393 143.730 98.537 90.385 -359.464 -113.345 12.386 Phase changes : 925 K, calculated boiling point of Cs to ideal monatomic gas; AH° ■ 16.198 kcal/mol. 997 K, II-I transition of Cs 2 S0 4 ; AH° = 0.072 kcal/mol. 1,278 K, melting point of Cs 2 S0 4 ; AH° = 8.47 kcal/mol. Sources: The enthalpy of formation at 298 K is from Wagman- (65) after correction for the heat of formation of the sulfate ion. The low-temperature heat capacities are from Paukov (51) , while the high-temperature enthalpy values are from Shmidt (56) and Denielou (12); see text. 31 [Formation: In 2 (S0 4 ) 3 (c) Indium sulfate 2In(c,l) + 3S(c,l) + 6 2 (g) = In 2 (S0 4 ) 3 (c) T, K cal/(mol«K) kcal/mol Log Kf c P u S° -(G° - H5 98 )/T TjO TjO" AHf° AGf° 298.15 65.704 72.240 72.240 -651.340 -570.120 417.904 300 65.972 72.647 72.240 .122 -651.350 -569.614 414.958 368.3 73.163 87.039 73.665 4.926 -651.489 -550.986 326.952 368.3 73.163 87.039 73.665 4.926 -651.777 -550.987 326.952 388.36 75.275 90.977 74.460 6.415 -651.780 -545.495 306.973 388.36 75.275 90.977 74.460 6.415 -653.019 -545.495 306.974 400 76.501 93.218 74.973 7.298 -653.062 -542.272 296.280 429.78 78.510 98.784 76.432 9.606 -653.170 -534.020 271.554 429.78 78.510 98.784 76.432 9.606 -654.730 -534.020 271.554 432.02 78.661 99.192 76.550 9.782 -654.768 -533.391 269.828 500 83.247 111.051 80.447 15.302 -655.223 -514.240 224.771 600 88.701 126.722 86.880 23.905 -655.125 -486.041 177.038 700 93.716 140.775 93.592 33.028 -654.470 -457.905 142.963 717.82 94.595 143.142 94.793 34.706 -654.297 -452.902 137.890 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH" = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 429.78 K, melting point of In; AH° = 0.780 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation at 298 K is from Barany (2^) after correction for the en- thalpy of formation of the sulfate ion. The entropy, heat capacity values, and high-temperature enthalpy values at 298 K are from Pankratz (46). [Formation: In 2 (S0 4 ) 3 (c) Indium sulfate 2In(c,l) + 1.5S 2 (g) + 6 2 (g) = In 2 (S0 4 ) 3 (c) ] T, K cal/(mol«K) kcal/mol Log Kf c P ° S° -(G° - Hl 98 )/T TjO TjO H "298 AHf° AGf° 298.15 65.704 72.240 72.240 -697.405 -598.661 438.825 300 65.792 72.647 72.240 .122 -697.406 -598.046 435.671 400 76.501 93.218 74.973 7.298 -697.015 -564.969 308.681 429.78 78.510 98.784 76.432 9.606 -696.785 -555.146 282.297 429.78 78.510 98.784 76.432 9.606 -698.345 -555.146 282.297 500 83.247 111.051 80.447 15.302 -697.606 -531.800 232.447 600 88.701 126.722 86.880 23.905 -696.208 -498.764 181.672 700 93.716 140.775 93.592 33.028 -694.445 -465.991 145.487 800 98.648 153.610 100.303 42.646 -692.318 -433.500 118.425 900 103.667 165.518 106.896 52.760 -689.799 -401.295 97.446 1,000 108.863 176.707 113.322 63.385 -686.857 -369.392 80.730 1,100 114.287 187.335 119.570 74.541 -683.468 -337.801 67.114 Phase changes : 429.78 K, melting point of In; AH C = 0.780 kcal/mol. Sources: The enthalpy of formation at 298 K is from Barany (2_) after correction for the en- thalpy of formation of the sulfate ion. The entropy, heat capacity values, and high-temperature enthalpy values at 298 K. are from Pankratz (46). 32 [Formation: K 2 S0 4 (c,l) Potassium sulfate 2K(c,l) + S(c,l) + 2 2 (g) = K 2 S0 4 (c,l) T, K cal/(mol«K) kcal/mol Log Kf Cp 4 S* -(G° - H2 98 )/T a H 298 AHf° AGf° OS -6.079 -341.109 -341.109 OO 100 18.928 14.725 66.295 -5.157 -342.567 -333.760 729.422 200 26.450 30.436 44.676 -2.848 -343.283 -324.639 354.745 298.15 31.386 41.956 41.956 -343.620 -315.406 231.196 300 31.469 42.150 41.957 .058 -343.624 -315.230 229.642 336.35 32.858 45.829 42.180 1.227 -343.711 -311.786 202.586 336.35 32.858 45.829 42.180 1.227 -344.827 -311.786 202.586 368.3 34.078 48.879 42.628 2.303 -344.877 -308.645 183.148 368.3 34.078 48.879 42.628 2.303 -344.973 -308.645 183.148 388.36 34.844 50.707 42.999 2.994 -344.992 -306.665 172.574 388.36 34.844 50.707 42.999 2.994 -345.405 -306.665 172.574 400 35.289 51.743 43.238 3.402 -345.428 -305.504 166.917 432.02 36.290 54.499 43.972 4.548 -345.488 -302.306 152.928 500 38.416 59.959 45.779 7.090 -345.625 -295.495 129.159 600 41.235 67.205 48.758 11.068 -345.466 -285.477 103.984 700 44.543 73.812 51.872 15.358 -344.964 -275.514 86.018 717.82 45.107 74.939 52.431 16.157 -344.838 -273.747 83.345 Phase changes: 336.35 K, melting point of K; AH" = 0.558 kcal/mol. 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° - 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Source: All data are from JANAF (16). 33 [Formation: K 2 S0 4 (c,l) Potassium sulfate 2K(c,l,g) + 0.5S 2 (g) + 2 2 (g) K 2 S0 4 (c,l)] T, K cal/(mol«K) kcal/mol Log Kf Cp a S° -(G° - H 298 )/T a u 298 AHf° AGf° 00 -6.079 -356.427 -356.427 00 100 18.928 14.725 66.295 -5.157 -358.087 -347.249 758.903 200 26.450 30.426 44.676 -2.848 -358.765 -336.101 367.269 298.15 31.386 41.956 41.956 -358.975 -324.920 238.170 300 31.469 42.150 41.957 .058 -358.976 -324.708 236.546 336.35 32.858 45.829 42.180 1.227 -359.004 -320.554 208.284 336.35 32.858 45.829 42.180 1.227 -360.120 -320.554 208.284 400 35.289 51.743 43.238 3.402 -360.079 -313.070 171.051 500 38.416 59.959 45.779 7.090 -359.753 -301.348 131.718 600 41.235 67.205 48.758 11.068 -359.160 -289.718 105.528 700 44.543 73.812 51.872 15.358 -358.289 -278.209 86.860 800 47.710 79.966 55.002 19.971 -357.132 -266.847 72.898 857 49.515 83.312 56.775 22.742 -356.345 -260.441 66.416 857 43.977 85.669 56.775 24.762 -354.325 -260.441 66.416 900 44.810 87.842 58.208 26.671 -353.923 -255.740 62.101 1,000 46.750 92.663 61.414 31.249 -352.885 -244.886 53.519 1,043.7 47.602 94.681 62.765 33.311 -352.387 -240.175 50.292 1,043.7 47.602 94.681 62.765 33.311 -390.463 -240.175 50.292 1,100 48.700 97.211 64.465 36.021 -389.513 -232.094 46.112 1,200 50.640 101.531 67.374 40.988 -387.686 -217.859 39.677 1,300 52.580 105.661 70.162 46.149 -385.684 -203.788 34.259 1,342 53.390 107.346 71.299 48.375 -384.791 -197.925 32.232 1,342 48.150 113.471 71.299 56.595 -376.571 -197.925 32.232 1,400 48.150 115.509 73.090 59.387 -375.626 -190.224 29.695 1,500 48.150 118.831 76.030 64.202 -374.008 -177.039 25.794 1,600 48.150 121.938 78.802 69.017 -372.408 -163.960 22.396 1,700 48.150 124.857 81.426 73.832 -370.820 -150.981 19.410 1,800 48.150 127.609 83.916 78.647 -369.251 -138.093 16.767 1,900 48.150 130.213 86.286 83.462 -367.698 -125.295 14.412 2,000 48.150 132.682 88.544 88.277 -366.161 -112.576 12.302 Phase changes 336.35 K, melting point of K; AH° = 0.558 kcal/mol. 857 K, cx-6 transition of K 2 S0 4 ; AH° = 2.020 kcal/mol. 1,043.7 K, calculated boiling point of K to ideal monatomic gas; AH° kcal/mol. 1,342 K, melting point of K 2 S0 4 ; AH° = 8.220 kcal/mol. 19.038 Source: All data are from JANAF (16). 34 [Formation: KAl(S0 4 ) 2 (c) Potassium aluminum sulfate K(c,l) + Al(c) + 2S(c,l) + 4 2 (g) = KAl(S0 4 ) 2 (c)] T, K cal/(mo] ■ •K) kcal/mol Log Kf c P ° S° -(G° - H^ 98 )/T u h 298 AHf° AGf° 00 -7.701 -585.069 -585.069 00 100 19.490 13.860 82.270 -6.841 -587.830 -571.043 1,247.998 200 35.490 32.680 52.850 -4.034 -589.655 -553.484 604.812 298.15 46.141 48.940 48.940 -590.560 -535.511 392.535 300 46.776 49.229 48.942 .086 -590.570 -535.169 389.865 336.35 49.844 54.754 49.278 1.842 -590.728 -528.448 343.365 336.35 49.844 54.754 49.278 1.842 -591.286 -528.448 343.365 368.3 52.541 59.526 49.958 3.524 -591.310 -522.478 310.035 368.3 52.541 59.526 49.958 3.524 -591.502 -522.478 310.035 388.36 54.234 62.359 50.527 4.595 -591.518 -518.717 291.904 388.36 54.234 62.359 50.527 4.595 -592.344 -518.717 291.905 400 55.217 63.975 50.895 5.232 -592.376 -516.510 282.204 432.02 56.807 68.288 52.026 7.026 -592.472 -510.434 258.215 500 60.184 76.867 54.829 11.019 -592.754 -497.493 217.451 600 63.782 88.171 59.463 17.225 -592.659 -478.439 174.269 700 66.735 98.231 64.297 23.754 -592.240 -459.432 143.439 717.82 67.200 99.914 65.160 24.947 -592.136 -456.052 138.849 Phase changes: = 0.096 kcal/mol. 336.35 K, melting point of K; AH° = 0.558 kcal/mol. 368.3 K, orthorhombic-monoclinic transformation of S; AH 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation at 298 K is from Wagman (65) after correction for the sul- fate ion. Low-temperature heat capacity and entropy values are from Kelley (30) . High-temper- ature enthalpy values are from Kelley (30). 35 [Formation: KAl(S0 4 ) 2 (c) Potassium aluminum sulfate K(c,l,g) + Al(c,l) + S 2 (g) + 4 2 (g) = KAl(S0 4 ) 2 (c)] T, K cal/(mo; ■•K) kcal/mol Log Kf Cp° S° -(G° - Hl 98 )/T no " tjO' H u 298 AHf° AGf° 00 -7.701 -615.705 -615.705 00 100 19.490 13.860 82.270 -6.841 -618.871 -598.023 1,306.961 200 35.490 32.680 52.850 -4.034 -620.620 -576.407 629.861 298.15 46.141 48.940 48.940 0.000 -621.270 -554.538 406.482 300 46.776 49.229 48.942 0.086 -621.274 -554.123 403.673 336.35 49.844 54.754 49.278 1.842 -621.313 -545.985 354.760 336.35 49.844 54.754 49.278 1.842 -621.872 -545.985 354.760 400 55.217 63.975 50.895 5.232 -621.678 -531.641 290.471 500 60.184 76.867 54.829 11.019 -621.009 -509.199 222.568 600 63.782 88.171 59.463 17.225 -620.048 -486.921 177.359 700 66.735 98.231 64.297 23.754 -618.890 -464.823 145.122 800 69.343 107.315 69.115 30.560 -617.578 -442.905 120.995 900 71.751 115.623 73.827 37.616 -616.130 -421.157 102.269 933.61 72.519 118.268 75.380 40.040 -615.616 -413.885 96.886 933.61 72.519 118.268 75.380 40.040 -618.196 -413.885 96.886 1,000 74.035 123.302 78.396 44.906 -617.106 -399.395 87.287 1,043.7 74.998 126.489 80.343 48.162 -616.351 -389.896 81.643 1,043.7 74.998 126.489 80.343 48.162 -635.389 -389.896 81.643 1,100 76.238 130.462 82.807 52.421 -634.238 376.682 74.839 Phase changes: 336.35 K, melting point of K; AH° = 0.558 kcal/mol. 933.61 K, melting point of Al; AH° = 2.580 kcal/mol. 1,043.7 K, calculated boiling point of K to ideal monatomic gas; AH C kcal/mol. = 19.038 Sources: The enthalpy of formation at 298 K is from Wagman (65) after correction for the sul- fate ion. Low-temperature heat capacity and entropy values are from Kelley (30) . High-temper- ature enthalpy values are from Kelley (30). [Formation: KAl(S0 4 ) 2 «12H 2 0(c) Potassium aluminum sulfate dodecahydrate K(c,l,g) + Al(c,l) + S(c,l) + 12 H 2 (g) + m o 2 (g) = KAl(S0 4 ) 2 -12H 2 0(c)] T, K cal/(mo; ■ •K) kcal/mol Log Kf Cp° S° -(G° - H° 298 )/T no _ rjO 11 u 298 AHf° AGf° 298.15 156.107 164.300 164.300 -1,448.960 -1,228.988 900.861 300 156.909 165.268 164.301 .290 -1,449.000 -1,227.622 894.311 336.35 172.528 184.094 165.426 6.279 -1,449.477 -1,200.766 780.211 336.35 172.528 184.094 165.426 6.279 -1,450.035 -1,200.766 780.211 350 178.393 191.074 166.291 8.674 -1,450.082 -1,190.648 743.464 358.99 182.218 195.646 166.968 10.295 -1,450.075 -1,183.983 720.789 Phase changes : 336.35 K, melting point of K; AH° = 0.558 kcal/mol. 358.99 K, melting point of KA1( S0 4 ) 2 - 12H 2 0(c) ; AH° = Sources: The enthalpy of formation at 298 K are from Wagmann (65) . mate (58) were matched to those of Gronvold (24). 22.8 kcal/mol. Heat capacities from Sho- 36 [Formation: Li 2 S0 4 (c,l) Lithium sulfate 2Li(c,l) + S(c,l) + 2 2 (g) = Li 2 S0 4 (c,l) T, K cal/(mol«K) kcal/mol Log Kf Cp° S 6 -(G° - H| 98 )/T » "298 AHf° AGf° 00 -4.454 -340.340 -340.340 00 100 10.485 6.915 46.995 -4.008 -341.684 -333.446 728.736 200 20.763 17.454 29.594 -2.428 -342.769 -324.746 354.861 298.15 28.109 27.234 27.234 -343.300 -315.767 231.461 300 28.209 27.408 27.235 .052 -343.306 -315.596 229.909 368.3 31.672 33.571 27.846 2.109 -343.430 -309.270 183.519 368.3 31.672 33.571 27.846 2.109 -343.526 -309.271 183.519 388.36 32.690 35.278 28.186 2.754 -343.545 -307.404 172.989 388.36 32.690 35.278 28.186 2.754 -343.958 -307.404 172.990 400 33.280 36.252 28.407 3.138 -343.982 -306.308 167.357 432.02 34.446 38.860 29.086 4.222 -344.058 -303.295 153.428 453.7 35.235 40.570 29.593 4.981 -344.179 -301.244 145.109 453.7 35.235 40.570 29.593 4.981 -345.613 -301.244 145.109 500 36.920 44.076 30.774 6.651 -345.704 -296.707 129.689 600 40.215 51.099 33.584 10.509 -345.639 -286.906 104.504 700 43.450 57.544 36.554 14.693 -345.211 -277.149 86.529 717.82 43.997 58.643 37.089 15.472 -345.097 -275.417 83.853 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° ■ 0.096 kcal/mol. 388.36 K, melting point of S; AH = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° ■ kcal/mol. 453.7 K, melting point of Li; AH° = 0.717 kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Source: All data are from JANAF (17). 37 [Formation: Li 2 S0 4 (c,l) Lithium sulfate 2Li(c,l,g) + 0.5S 2 (g) + 2 2 (g) = Li 2 S0 4 (c,l)] T, K cal/(mol«K) kcal/mol Log Kf Cp u S° -(G° - Hi 98 )/T H° - H 2 98 AHf° AGf° 00 -4.454 -355.658 -355.658 00 100 , 10.485 6.915 46.995 -4.008 -357.204 -346.936 758.217 200 20.763 17.454 29.594 -2.428 -358.251 -336.207 367.386 298.15 28.109 27.234 27.234 -358.655 -325.281 238.434 300 28.209 27.408 27.235 .052 -358.658 -325.074 236.813 400 33.280 36.252 28.407 3.138 -358.633 -313.874 171.490 453.7 35.235 40.570 29.593 4.981 -358.522 -307.874 148.303 453.7 35.235 40.570 29.593 4.981 -359.956 -307.874 148.303 500 36.920 44.076 30.774 6.651 -359.831 -302.561 132.247 600 40.215 51.099 33.584 10.509 -359.333 -291.146 106.049 700 43.450 57.544 36.554 14.693 -358.536 -279.844 87.370 800 46.520 63.531 39.555 19.181 -357.464 -268.673 73.397 848 48.454 66.296 40.991 21.459 -356.837 -263.363 67.874 8^8 51.000 74.315 40.991 28.259 -350.037 -263.363 67.874 900 51.000 77.351 43.005 30.911 -349.183 -258.075 62.668 1,000 51.000 82.724 46.713 36.011 -347.561 -248.038 54.208 1,100 51.000 87.585 50.211 41.111 -345.962 -238.162 47.318 1,132 51.000 89.047 51.288 42.743 -345.455 -235.033 45.376 1,132 49.000 90.858 51.288 44.793 -343.405 -253.033 45.376 1,200 49.000 93.717 53.613 48.125 -342.471 -228.552 41.625 1,300 49.000 97.639 56.851 53.025 -341.110 -219.115 36.836 1,400 49.000 101.270 59.895 57.925 -339.767 -209.781 32.748 1,500 49.000 104.651 62.768 62.825 -338.434 -200.545 29.219 1,600 49.000 107.813 65.485 67.725 -337.116 -191.393 26.143 1,638 49.000 108.963 66.480 69.587 -336.617 -187.939 25.075 1,638 49.000 108.963 66.480 69.587 -406.937 -187.940 25.075 1,700 49.000 110.784 68.063 72.625 -405.905 -179.665 23.097 1,800 49.000 113.584 70.515 77.525 -404.247 -166.402 20.204 1,900 49.000 116.234 72.852 82.425 -402.607 -153.237 17.626 2,000 49.000 118.747 75.085 87.325 -400.979 -140.151 15.315 Phase changes : 453.7 K, melting point of Li; AH = 0.717 kcal/mol. 848 K, ct-B transition point for Li 2 S0 4 (c), AH = 6.80 kcal/mol. 1,132 K, melting point of Li 2 S0 4 (c) , AH° = 2.050 kcal/mol. 1,638 K, calculated boiling point of Li to ideal monatomic gas; AH e kcal/mol. = 35.160 Source: All data from JANAF (17). 38 Li 2 S0 4 'H 2 0(c) Lithium sulfate monohydrate [Formation: 2Li(c,l) + S(c,l) + 2.5 2 (g) + I l 2 (g) = Li 2 S0 4 •H 2 0(c)] T, K cal/(mol«K) kcal/mol Log Kf ■- p B S° -(G° - H2 98 )/T H H 298 AHf° AGf° OO -5.697 -409.751 -409.751 OO 100 13.360 9.067 60.217 -5.115 -412.023 -399.526 873.152 200 26.490 22.512 38.012 -3.100 -413.665 -386.329 422.156 298.'15 36.100 34.995 34.995 -414.530 -372.701 273.194 300 36.248 35.219 34.996 .067 -414.541 -372.442 271.320 350 39.772 41.083 35.452 1.971 -414.742 -365.407 228.167 368.3 40.728 43.134 35.783 2.708 -414.795 -362.826 215.299 368.3 40.728 43.134 35.783 2.708 -414.891 -362.826 215.299 388.36 41.776 45.331 36.218 3.539 -414.935 -359.987 202.580 388.36 41.776 45.331 36.218 3.539 -415.348 -359.987 202.581 400 42.384 46.574 36.502 4.029 -415.389 -358.327 195.779 432.02 43.473 49.889 37.374 5.407 -415.511 -353.761 178.958 450 44.084 51.674 37.910 6.194 -415.646 -351.188 170.558 453.7 44.142 52.035 38.023 6.357 -415.671 -350.658 168.912 453.7 44.142 52.035 38.023 6.357 -417.105 -350.658 168.912 500 44.872 56.367 39.523 8.422 -417.296 -343.862 150.300 550 44.748 60.645 41.250 10.667 -417.490 -336.507 133.714 Phase ch anges : 36 8.3 K, orl :hrhomibc-monoclii lie transformation of S; AH' ' = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 453.7 K, melting point of Li; AH° = 0.717 kcal/mol, Sources: The enthalpy of formation is based on Barany (3). Low-temperature heat capacities and entropies are from Paukov (53). High-temperature enthalpies are estimated. 39 [Formation: MgS0 4 (6,c,l) Magnesium sulfate (8,c,l) Mg(c,l,g) + 0.5S 2 (g) + 2 2 (g) = MgS0 4 ($,c,l)] T, K cal/(mol •K) kcal/mol Log Kf Cp* S° -(G° - H° 298 )/T TjO TJO H H 298 AHf° AGf u 00 -3.678 -319.706 -319.706 00 100 8.679 4.775 38.315 -3.354 -321.290 -310.932 679.532 200 17.521 13.751 23.791 -2.008 -322.253 -300.259 328.104 298.15 23.000 21.844 21.844 -322.465 -289.302 212.061 300 23.050 21.987 21.844 .043 -322.466 -289.094 210.602 400 26.290 29.085 22.790 2.518 -322.420 -277.973 151.875 500 28.540 35.199 24.675 5.262 -322.190 -266.886 116.654 600 30.500 40.581 26.886 8.217 -321.835 -255.853 93.193 700 32.100 45.404 29.193 11.348 -321.385 -244.889 76.457 800 33.580 49.788 31.497 14.633 -320.853 -234.001 63.925 900 34.950 53.823 33.756 18.060 -320.245 -223.175 54.194 922 35.236 54.671 34.245 18.832 -320.101 -220.808 52.339 922 35.236 54.671 34.245 18.832 -322.240 -220.808 52.339 1,000 36.250 57.574 35.953 21.621 -321.699 -212.254 46.388 1,100 37.450 61.086 38.081 25.306 -320.939 -201.349 40.004 1,200 38.580 64.394 40.136 29.109 -320.113 -190.514 34.697 1,300 39.520 67.520 42.123 33.016 -319.223 -179.737 30.216 1,363 40.012 69.402 43.341 35.522 -318.643 -173.009 27.741 1,363 40.012 69.402 43.341 35.522 -348.893 -173.009 27.741 1,400 40.301 70.478 44.044 37.008 -348.401 -168.244 26.264 1,400 38.000 73.034 44.044 40.586 -344.823 -168.244 26.264 1,500 38.000 75.656 46.065 44.386 -343.723 -155.673 22.681 1,600 38.000 78.108 47.992 48.186 -342.639 -143.170 19.556 1,700 38.000 80.412 49.832 51.986 -341.569 -130.736 16.807 1,800 38.000 82.584 51.592 55.786 -340.513 -118.362 14.371 1,900 38.000 84.639 53.278 59.586 -339.474 -106.050 12.198 2,000 38.000 86.588 54.895 63.386 -338.447 -93.791 10.249 Phase changes 922 K, melting point of Mg ; AH = 2 . 1 39 kcal/mol . 1,363 K, boiling point of Mg; AH = 30.250 kcal/mol. 1,400 K, melting point of MgS0 4 ; AH° = 3.5 kcal/mol. Sources: The enthalpy of formation All other data are from JANAF (15). is based on Ko (34) after correction for the sulfate ion. 40 [Formation: MgS0 4 (a,c) Magnesium sulfate (ot,c) Mg(c) + S(c,l) + 2 2 (g) = MgS0 4 (a,c)] T, K cal/(mol*K) kcal/mol Log Kf Cp° S° -(G u - H5 98 )/T TjO Tj3 °- "298 AHf° AGf° CO -3.678 -305.308 -305.308 OO 100 8.679 4.775 38.315 -3.354 -306.690 -298.362 652.061 200 17.521 13.751 23.791 -2.008 -307.691 -289.718 316.585 298.15 23.000 21.844 21.844 -308.030 -280.708 205.762 300 23.050 21.987 21.844 .043 -308.034 -280.537 204.369 368.3 25.263 26.957 22.339 1.701 -308.139 -274.265 162.747 368.3 25.263 26.957 22.339 1.701 -308.235 -274.265 162.747 388.36 25.913 28.314 22.613 2.214 -308.252 -272.414 153.299 388.36 25.913 28.314 22.613 2.214 -308.665 -272.414 153.299 400 26.290 29.085 22.790 2.518 -308.689 -271.327 148.244 432.02 27.010 31.137 23.334 3.371 -308.763 -268.334 135.743 500 28.540 35.199 24.675 5.262 -308.983 -261.953 114.498 600 30.500 40.581 26.886 8.217 -309.061 -252.532 91.984 700 32.100 45.404 29.193 11.348 -308.980 -243.114 75.903 717.82 32.364 46.214 29.605 11.922 -308.951 -241.437 73,508 Phase changes 368.3 K, orthorhombic-monoclinic transformation of S; AH ■ 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation is based on Ko ( 34 ) after correction for the sulfate ion. All other data are from JANAF (15). 41 [Formation: MgS0 4 (a,c,l) Magnesium sulfate (ct,c,l) Mg(c,l,g) + 0.5S 2 (g) + 2 2 (g) = MgS0 4 (a,c,l)] T, K cal/(mol«K) kcal/mol Log Kf c P u S° -(G u - H$ 98 )/T H tt 298 AHf° AGf° 00 -3.678 -320.626 -320.626 00 100 8.679 4.775 38.315 -3.354 -322.211 -311.852 681.543 200 17.521 13.751 23.791 -2.008 -323.173 -301.179 329.109 298.15 23.000 21.844 21.844 -323.385 -290.222 212.736 300 23.050 21.987 21.844 .043 -323.386 -290.014 211.273 400 26.290 29.085 22.790 2.518 -323.340 -278.893 152.378 500 28.540 35.199 24.675 5.262 -323.111 -267.806 117.057 600 30.500 40.581 26.886 8.217 -322.755 -256.773 93.528 700 32.100 45.404 29.193 11.348 -322.305 -245.809 76.744 800 33.580 49.788 31.497 14.633 -321.773 -234.921 64.177 900 34.950 53.823 33.756 18.060 -321.165 -224.095 54.417 922 35.236 54.671 34.245 18.832 -321.021 -221.728 52.558 922 35.236 54.671 34.245 18.832 -323.160 -221.728 52.558 1,000 36.250 57.574 35.953 21.621 -322.619 -213.174 46.589 1,100 37.450 61.086 38.081 25.306 -321.859 -202.269 40.187 1,200 38.580 64.394 40.136 29.109 -321.034 -191.434 34.864 1,300 39.520 67.520 42.123 33.016 -320.143 -180.657 30.371 1,363 40.012 69.402 43.341 35.522 -319.563 -173.929 27,888 1,363 40.012 69.402 43.341 35.522 -349.813 -173.929 27.888 1,400 40.301 70.478 44.044 37.008 -349.322 -169.164 26.407 1,400 38.000 73.034 44.044 40.586 -345.743 -169.164 26.407 1,500 38.000 75.656 46.065 44.386 -344.643 -156.593 22.815 1,600 38.000 78.108 47.992 48.186 -343.559 -144.090 19.682 1,700 38.000 80.412 49.832 51.986 -342.490 -131.656 16.925 1,800 38.000 82.584 51.592 55.786 -341.434 -119.282 14.483 1,900 38.000 84.639 53.278 59.586 -340.394 -106.970 12.304 2,000 38.000 86.588 54.895 63.386 -339.367 -94.711 10.349 Phase changes: 922 K, melting point of Mg; AH° = 2.139 kcal/mol. 1,363 K, boiling point of Mg; AH° = 30.250 kcal/mol. 1,400 K, melting point of MgS0 4 ; AH° = 3.5 kcal/mol. Sources: The enthalpy of formation is based on Ko ( 34 ) after correction for the sulfate ion. All other data are from JANAF (15). 42 MgS0 4 (8,c) Magnesium sulfate (g,c) [Formation: Mg(c) + S(c,l) + 2 2 (g) = MgS0 4 (B,c)] T, K cal/(mol«K) kcal/mol Log Kf Cp u S° -(6" - H5 ga )/T a. u 298 AHf u AGf° -3.678 -304.388 -304.388 100 8.679 4.775 38.315 -3.354 -305.770 -297.442 650.051 200, 17.521 13.751 23.791 -2.008 -306.771 -288.798 315.579 298.15 23.000 21.844 21.844 -307.110 -279.788 205.088 300 23.050 21.987 21.844 .043 -307.114 -279.617 203.698 368.3 25.263 26.957 22.339 1.701 -307.219 -273.345 162.201 368.3 25.263 26.957 22.339 1.701 -307.315 -273.345 162.202 388.36 25.913 28.314 22.613 2.214 -307.332 -271.494 152.781 388.36 25.913 28.314 22.613 2.214 -307.745 -271.494 152.782 400 26.290 29.085 22.790 2.518 -307.769 -270.407 147.742 432.02 27.010 31.137 23.334 3.371 -307.843 -267.414 135.278 500 28.540 35.199 24.675 5.262 -308.063 -261.033 114.096 600 30.500 40.581 26.886 8.217 -308.141 -251.612 91.648 700 32.100 45.404 29.193 11.348 -308.060 -242.194 75.615 717.82 32.364 46.214 29.605 11.922 -308.031 -240.517 73.228 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation All other data are from JANAF (15). is based on Ko (34) after correction for the sulfate ion. [Formation: MgS0 4 -H 2 0(c) Magnesium sulfate monohydrate Mg(c) + S(c,l) + 2.5 2 (g) + H 2 (g) = MgS0 4 -H 2 0(c)] T, K cal/(mol«K) kcal/mol Log Kf c P ° S° -(G° - H^ 98 )/T a «298 AHf° AGf° 298.15 34.600 30.200 30.200 -384.800 -343.360 251.686 300 34.767 30.415 30.202 .064 -384.802 -343.102 249.946 350 39.274 36.112 30.641 1.915 -384.759 -336.154 209.901 368.3 40.923 38.156 30.964 2.649 -384.695 -333.614 197.964 368.3 40.923 38.156 30.964 2.649 -384.792 -333.614 197.964 388.36 42.731 40.374 31.391 3.489 -384.693 -330.827 186.171 388.36 42.731 40.374 31.391 3.489 -385.106 -330.827 186.171 400 43.780 41.651 31.671 3.992 -385.053 -329.201 179.865 4332.02 46.666 45.132 32.542 5.439 -384.873 -324.738 164.276 450 48.287 47.068 33.084 6.293 -384.810 -322.239 156.499 500 52.794 52.388 34.748 8.820 -384.328 -315.309 137.820 550 57.301 57.631 36.589 11.573 -383.626 -308.435 122.559 Phase changes: 368.3 K, orthrhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. Sources: The enthalpy of formation is based on Ko (34) after correction for the sulfate ion. The entropy at 298 K is from Parker (49). The heat capacity estimates are based on Rolla (54). 43 [Formation: MgS0 4 -2H 2 0(c) Magnesium sulfate dihydrate Mg(c) + S(c,l) + 3 2 (g) + 2H 2 (g) = MgS0 4 -2H 2 0(c)] T, K cal/(mol'K) kcal/mol Log Kf Cp° S° -(G° - H^ 98 )/T TjO tjO H "298 AHf° AGf° 298.15 42.000 40.000 40.000 -453.300 -398.172 291.864 300 42.185 40.260 40.000 .078 -453.308 -397.828 289.814 350 47.193 47.139 40.533 2.312 -453.404 -388.573 242.633 368.3 49.026 49.591 40.923 3.192 -453.386 -385.183 228.566 368.3 49.026 49.591 40.923 3.192 -453.482 -385.183 228.566 388.36 51.034 52.244 41.439 4.196 -453.431 -381.464 214.666 388.36 51.034 52.244 41.439 4.196 -453.844 -381.464 214.666 400 52.200 53.768 41.776 4.797 -453.817 -379.295 207.234 432.02 55.407 57.909 42.818 6.520 -453.700 -373.334 188.859 450 57.208 60.205 43.467 7.532 -453.670 -369.992 179.690 500 62.215 66.492 45.456 10.518 -453.263 -360.713 157.665 550 67.223 72.657 47.650 13.754 -452.615 -351.484 139.665 Phase chnages : 368.3 K, orthrhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. Sources: The enthalpy of formation is from Parker ( 49 ) after correction for the sulfate ion. The heat capacity and entropy values are estimates. MgS0 4 -4H 2 0(c) Magnesium sulfate tetrahydrate [Formation: Mg(c) + S(c,l) + 4 2 (g) + 4H 2 (g) = MgS0 4 ^H^c) ] T, K cal/(mo] •K) kcal/mol Log Kf c P ° S° -(G° - H| 98 )/T no tjO H H 2g8 AHf° AGf° 298.15 60.000 59.000 59.000 -596.800 -514.117 376.853 300 60.259 59.372 59.002 .111 -596.814 -513.603 374.155 350 67.270 69.187 59.761 3 9^ ^7.001 -499.717 312.033 368.3 69.836 72.681 60.317 . ■596.993 -494. 6 Ju 293.510 368.3 69.836 72.681 60.317 4.554 -597.089 -494.630 293.510 388.36 72.648 76.458 61.053 5.983 -597.036 -489.050 275.210 388.36 72.648 76.458 61.053 5.983 -597.449 -489.050 275.210 400 74.280 78.628 61.533 6.838 -597.413 -485.801 265.426 432.02 78.770 84.518 63.016 9.289 -597.246 -476.872 241.236 450 81.291 87.781 63.941 10.728 -597.173 -471.866 229.166 500 88.301 69.709 66.775 14.967 -596.580 -457.972 200.176 550 85.312 105.454 69.894 19.558 -595.651 -444.149 176.486 Phase changes: 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 388.36 K, melting point of S; AH° 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol 0.096 kcal/mol. Sources: The enthalpy of formation is from Parker (49) after correction for the sulfate ion. The heat capacity and entropy values are estimates. 44 [Formation: MgS0 4 '6H 2 0(c) Magnesium sulfate hexahydrate Mg(c) + S(c,l) + 5 2 (g) + 6H 2 (g) MgS0 4 -6H 2 0(c) T, K cal/(mo. L-K) kcal/mol Log Kf c P ° S° -(G° - H° 298 )/T no"" ii°"~~ H H 298 AHf° AGf° 00 -13.244 -726.355 -726.355 OS 100 31.810 23.110 141.340 -11.823 -733.024 -699.682 1,529.135 200 61.130 54.500 90.120 -7.124 -736.624 -664.853 726.508 298.15 83.200 83.200 83.200 -737.880 -629.193 461.205 300 83.573 83.716 83.203 .154 737.890 -628.518 457.869 350 93.090 97.327 84.256 4.575 -737.889 -610.283 381.073 368.3 96.175 102.150 85.026 6.307 -737.789 -603.614 358.181 368.3 96.175 102.150 85.026 6.307 -737.885 -603.614 358.181 388.36 99.557 107.351 86.044 8.275 -737.715 -596.304 335.566 388.36 99.557 107.351 86.044 8.275 -738.128 -596.304 335.566 400 101.520 110.320 86.708 9.445 -738.023 -592.055 323.479 432.02 106.223 118.327 88.756 12.775 -737.655 -580.384 293.600 450 108.864 122.712 90.025 14.709 -737.470 -573.845 278.694 500 115.121 134.516 93.890 20.313 -736.580 -555.709 242.897 550 120.291 145.739 98.097 26.203 -735.426 -537.672 213.648 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. Sources: The enthalpy of formation is from Parker (49) after correction for the sulfate ion. The low-temperature heat capacity and entropy values are from Cox (10) , while the high-temper- ature enthalpy values are extrapolated. [Formation: MgS0 4 -7H 2 0(c) Magnesium sulfate heptahydrate Mg(c) + S(c,l) + 5.5 2 (g) + 7H 2 (g) = MgS0 4 -7H 2 0(c) ] T, K cal/(mo! L-K) kcal/mol Log Kf c P a S° -(G° - H| 98 )/T TjO Tjfl "■ H 298 AHf° AGf° 298.15 91.000 89.000 89.000 0.000 -810.000 -686.432 503.162 300 91.463 89.564 89.001 0.169 -810.014 -685.664 499.500 350 103.982 104.604 90.161 5.055 -810.071 -644.927 415.194 368.3 108.564 110.020 91.014 7.000 -809.950 -657.341 390.062 368.3 108.564 110.020 91.014 7.000 -810.046 -657.341 390.062 388.36 113.587 115.909 92.147 9.228 -809.827 -649.028 365.236 388.36 113.587 115.909 92.147 9.228 -810.240 -649.028 365.236 400 116.501 119.306 92.889 10.567 -810.089 -644.199 351.969 432.02 124.518 128.581 95.190 14.426 -809.533 -630.939 319.175 450 129.020 133.750 96.628 16.705 -809.193 -623.516 302.817 500 141.538 147.992 101.054 23.469 -807.677 -602.961 263.551 550 154.057 162.069 105.962 30.859 -805.560 -582.583 231.494 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. Sources: The enthalpy of formation and entropy at 298 K are from Parker (49) after correction for the sulfate ion. The heat capacity values are estimates based on Rolla (54). 45 [Formation: Na 2 S0 4 (c) Sodium sulfate 2Na(c,l) + S(c,l) + 2 2 (g) = Na 2 S0 4 (c) T, K cal/(mol«K) kcal/mol Log Kf c P u S° -(G° - H5 98 )/T no _ WO a _ 1*298 AHf° AGf° 00 -5.549 -328.959 -328.959 00 100 15.904 10.306 59.036 -4.873 -330.475 -321.789 703.261 200 25.255 24.620 38.390 -2.754 -331.315 -312.732 341.733 298.15 30.627 35.754 35.754 -331.696 -303.517 222.481 300 30.711 35.944 35.754 .057 -331.699 -303.340 220.980 368.3 33.422 42.529 36.412 2.253 -331.819 -296.872 176.162 368.3 33.422 42.529 36.412 2.253 -331.915 -296.872 176.162 371 33.529 42.773 36.458 2.343 -331.919 -296.615 174.729 371 33.529 42.773 36.458 2.343 -333.163 -296.615 174.729 388.36 34.218 44.323 36.776 2.931 -333.189 -294.904 165.955 388.36 34.218 44.323 36.776 2.931 -333.602 -294.904 165.955 400 34.680 45.340 37.010 3.332 -333.632 -293.744 160.492 432.02 35.766 48.055 37.728 4.461 -333.709 -290.548 146.980 458 36.647 50.169 38.374 5.402 -333.847 -287.947 137.402 458 36.647 50.302 38.374 5.463 -333.786 -287.947 137.402 500 37.980 53.575 39.515 7.030 -333.815 -283.742 124.022 514 38.411 54.630 39.912 7.565 -333.819 -282.340 120.048 514 40.806 59.726 39.912 10.185 -331.199 -282.340 120.048 600 41.905 66.121 43.231 13.734 -330.920 -274.192 99.873 700 43.270 72.682 46.981 17.991 -330.431 -264.777 82.666 717.82 43.536 73.773 47.632 18.764 -330.325 -263.106 80.105 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 371 K, melting point of Na; AH° = 0.622 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 458 K, V-IV transition of Na 2 S0 4 ; AH° - 0.061 kcal/mol. 514 K, IV-I transition of Na 2 S0 4 ; AH - 2.607 kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Source: All data are from JANAF (16). 46 [Formation: Na 2 S0 4 (c,l) Sodium sulfate 2Na(c,l,g) + 0.5S 2 (g) + 2 2 (g) = Na 2 S0 4 (c,l)] T, K cal/(moI ■ •K) kcal/mol Log Kf Cp° S° -(G° - H5 98 )/T u ° ZZ u a 0. ti 2 98 AHf u AGf° 00 -5.549 -344.277 -344.277 oa 100 15.904 10.306 59.036 -4.873 -345.996 -335.279 732.743 200 25.255 24.620 38.390 -2.754 -346.798 -324.194 354.258 298.15 30.627 35.754 35.754 -347.051 -313.031 229.455 300 30.711 35.944 35.754 .057 -347.051 -312.818 227.885 371 33.529 42.773 36.458 2.343 -347.057 -304.716 179.500 371 33.529 42.773 36.458 2.343 -348.301 -304.716 179.501 400 34.680 45.340 37.010 3.332 -348.283 -301.309 164.626 458 36.647 50.169 38.374 5.402 -348.097 -294.503 140.530 458 36.647 50.302 38.374 5.463 -347.943 -294.503 140.530 500 37.980 53.575 39.515 7.030 -347.943 -289.595 126.580 514 38.411 54.630 39.912 7.565 -347.879 -287.962 122.438 514 40.806 59.726 39.911 10.185 -345.259 -287.962 122.438 600 41.905 66.121 43.231 13.734 -344.615 -278.433 101.418 700 43.270 72.682 46.981 17.991 -343.756 -267.472 83.507 800 44.760 78.556 50.566 22.392 -342.777 -256.639 70.110 900 46.330 83.919 53.978 26.947 -341.670 -245.937 59.721 1,000 47.875 88.880 57.223 31.657 -340.437 -235.365 51.438 1,100 49.410 93.515 60.313 36.522 -339.090 -224.923 44.687 1,157 50.279 96.033 62.005 39.370 -338.259 -219.012 41.369 1,157 47.092 100.960 62.006 45.070 -332.559 -219.012 41.369 1,177 47.092 101.767 62.675 46.012 -332.331 -217.052 40.302 1,177 47.092 101.767 62.675 46.012 -378.901 -217.052 40.302 1,200 47.092 102.678 63.438 47.088 -378.552 -213.903 38.957 1,300 47.092 106.448 66.604 51.797 -377.002 -200.242 33.663 1,400 47.092 109.938 69.577 56.506 -375.474 -186.705 29.146 1,500 47.092 113.187 72.377 61.215 -373.961 -173.278 25.246 1,600 47.092 116.226 75.023 65.925 -372.464 -159.946 21.847 1,700 47.092 119.081 77.532 70.634 -370.983 -146.709 18.860 1,800 47.092 121.773 79.916 75.343 -369.516 -133.558 16.216 1,900 47.092 124.319 82.186 80.052 -368.064 -120.489 13.859 2,000 47.092 126.734 84.354 84.761 -366.626 -107.495 11.746 Phase changes : 371 K, melting point of Na; AH° = 0.622 kcal/mol. AH = 0.061 kcal/mol. AH = 2.607 kcal/mol. AH° = 5.700 kcal/mol. 1,177 K, boiling point of Na to ideal monatomic gas; AH Source: All data re from JANAF (16). 458 K, V-IV transition of Na 2 S0 4 514 K, IV-I transition of Na 2 S0 4 1,157 K, melting point of Na 2 S0 4 23.285 kcal/mol. 47 [Formation: Na 2 SO 4 '10H 2 O(c) Sodium sulfate decahydrate 2Na(c,l) + S(c,l) + 10H 2 (g) + 7 2 (g) = Na 2 S0 4 -10H 2 0(c) ] T, K cal/(mol«K) kcal/mol Log Kf Cp° S° -(G° - H° 298 )/T TjO ~ TTO H. H 298 AHf° AGf^ 298.15 124.000 141.500 141.500 -1,034.240 -871.491 638.812 300 124.666 142.269 141.502 .230 -1,034.265 -870.480 634.136 350 142.666 162.838 143.087 6.913 -1,034.487 -843.154 526.482 368.3 149.254 170.277 144.254 9.584 -1,034.373 -833.152 494.387 368.3 149.254 170.277 144.254 9.584 -1,034.469 -833.152 494.388 371 150.226 171.371 144.448 9.988 -1,034.444 -831.677 489.920 371 150.226 171.371 144.448 9.988 -1,035.688 -831.677 489.921 388.36 156.476 178.381 145.805 12.651 -1,035.468 -822.133 462.650 388.36 156.476 178.381 145.805 12.651 -1,035.881 -822.133 462.650 400 160.666 183.064 146.822 14.497 -1,035.696 -815.729 445.688 432.02 172.193 195.874 149.983 19.826 -1,034.966 -798.147 403.761 450 178.666 203.027 151.960 22.980 -1,034.477 -788.302 382.847 500 196.666 222.783 158.057 32.363 -1,032.356 -761.054 332.652 550 214.666 242.371 164.831 42.647 -1,029.352 -734.062 291.685 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 371 K, melting point of Na; AH° = 0.622 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. Source: The enthalpy of formation and entropy at 298 K are from Wagman ( 65 ) after the sulfate correction. Heat capacity values are estimated. [Formation: (NH 4 ) 2 S0 4 (c) Ammonium sulfate N 2 (g) + 4H 2 (g) + S(c,l) + 2 2 (g) = (NH 4 ) 2 S0 4 (c)] T, K cal/(mol«K) kcal/mol Log Kf c P ° S° -(G° - H 298 )/T nO ' ttO 11 tt 298 AHf° AGf° OO -8.512 -275.800 -275.800 00 100 19.024 13.672 90.382 -7.671 -280.072 -259.425 566.965 200 43.996 33.445 56.875 -4.686 -282.144 -237.807 259.860 298.15 44.812 52.710 52.710 -282.660 -216.006 158.335 300 44.936 52.988 52.711 .083 -282.678 -215.593 157.057 368.3 49.349 62.645 53.673 3.304 -283.175 -200.261 118.834 368.3 49.349 62.645 53.673 3.304 -283.271 -200.261 118.834 388.36 50.645 65.297 54.207 4.307 -283.373 -195.736 110.149 388.36 50.645 65.297 54.207 4.307 -283.786 -195.737 110.149 400 51.397 66.804 54.552 4.901 -283.853 -193.097 105.502 432.02 53.567 70.845 55.611 6.581 -284.017 -185.826 94.004 500 58.173 78.988 58.240 10.374 -284.278 -170.348 74.458 600 65.745 90.250 62.647 16.562 -283.970 -147.579 53.755 650 69.886 95.674 64.979 19.952 -283.522 -136.229 45.804 Phase changes 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH = kcal/mol. Sources: The enthalpy of formation at 298 K is from Parker (50) after correction for the SO^" ion. The entropy at 298 K is based on Kelley (30) . Low-temperature heat capacity values and high-temperature enthalpies are from Kelley (30); see text. 48 NH 4 Al(S0 4 ) 2 (c) Ammonium aluminum sulfate [Formation: 0.5N 2 (g) + 2H 2 (g) + Al(c,l) + 2S(c) + 4 2 (g) = NH 4 A1(S0 4 ) 2 (c) ] T, K cal/(mol«K) kcal/mol Log Kf Cp° S° -(6° - H° 298 )/T tjO 7Tb H - H 298 AHf° AGf° oo -8.620 -554.437 -554.437 00 100 20.215 11.852 90.282 -7.843 -558.648 -535.793 1,170.959 200 40.973 32.717 56.282 -4.713 -561.166 -511.855 559.322 298.15 54.114 51.715 51.715 -562.400 -487.355 357.236 300 54.315 52.050 51.717 .100 -562.416 -486.889 354.694 368.3 61.840 64.370 52.916 4.218 -562.586 -469.661 278.694 368.3 61.840 64.370 52.916 4.218 -562.778 -469.661 278.694 388.36 64.051 67.710 53.596 5.481 -562.799 -464.588 261.444 388.36 64.051 67.710 53.596 5.481 -563.625 -464.588 261.444 400 65.333 69.620 54.035 6.234 -563.656 -461.620 252.214 432.02 66.768 74.706 55.381 8.349 -563.750 -453.449 229.388 500 69.816 84.730 58.700 13.015 -564.047 -436.059 190.599 600 72.512 97.714 64.147 20.140 -564.063 -410.454 149.506 650 73.552 103.560 66.957 23.792 -563.985 -397.656 133.702 Phase changes: 368.3 K, orthrhombic-monocTinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. Source: See text. [Formation: NH 4 Al(S0 4 ) 2 «12H 2 0(c) Ammonium aluminum sulfate dodecahydrate 0.5N 2 (g) + 14H 2 (g) + Al(c) + 10 2 (g) = NH 4 A1(S0 4 ) 2 -12H 2 0(c) ] T, K cal/(mol«K) kcal/mol Log Kf Cp 6 S° -CG° - Hi 98 )/T TjO Tj6" 11 "298 AHf° AGf° 298.15 162.962 166.600 166.600 -1,420.420 -1,180.311 865.180 300 163.740 167.610 166.603 .302 -1,420.468 -1,178.821 858.759 350 183.761 194.379 168.670 8.998 -1,421.170 -1,138.476 710.887 367.13 190.175 203.313 170.080 12.201 -1,421.212 -1,124.638 669.480 Phase changes : 367.13 K, melting point of NH 4 A1(S0 4 ) 2 «12H 2 0(c) ; AH° - 29.16 kcal/mol, Sources: The enthalpy of formation and entropy at 298 K are from Wagman (63) after correction for the sulfate ion. Heat capacity values are from Kelley (30) and Gronvold (24). 49 [Formation: PbS0 4 (c) Lead sulfate Pb(c,l) + S(c,l) + 2 2 (g) = PbS0 4 (c) T, K cal/(mol*K) kcal/mol Log Kf Cp° S° -(G° - H 298 )/T TjO TjO H u 2?8 AHf° AGf° 00 -4.792 -217.814 -217.814 00 100 14.408 14.516 54.396 -3.988 -218.985 -210.978 461.086 200 20.356 26.492 37.632 -2.228 -220.849 -203.936 222.848 298.15 24.667 35.490 35.490 -219.870 -194.327 142.444 300 24.717 35.636 35.489 .044 -219.874 -194.168 141.449 368.3 25.502 40.612 35.992 1.702 -220.003 -188.302 111.737 368.3 25.502 40.612 35.992 1.702 -220.099 -188.302 111.737 388.36 25.733 41.971 36.266 2.216 -220.121 -186.569 104.990 388.36 25.733 41.971 36.266 2.216 -220.534 -186.569 104.990 400 25.867 42.733 36.443 2.516 -220.565 -185.551 101.379 432.02 26.674 44.756 36.985 3.357 -220.660 -182.745 92.445 500 28.388 48.772 38.318 5.227 -220.918 -176.754 77.258 600 31.033 54.180 40.518 8.197 -221.008 -167.910 61.161 600.65 31.051 54.214 40.533 8.217 -221.007 -167.851 61.073 600.65 31.051 54.214 40.533 8.217 -222.154 -167.851 61.073 600 33.735 59.167 42.831 11.435 -221.999 -158.879 49.604 717.82 34.222 60.021 43.247 12.040 -221.941 -157.273 47.883 Phase changes : 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 600.65 K, melting point of Pb; AH° » 1.147 kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation and entropy at 298 K are from CODATA (7) . Low-temperature heat capacity values are from Gallagher ( 21 ) , while high-temperature enthalpy values are from Krestovnikov (35). [Formation: PbS0 4 (c) Lead sulfate Pb(c,l) + 0.5S 2 (g) + 2 2 (g) = PbS0 4 (c) T, K cal/(mol«K) kcal/mol Log Kf c P ° S° -(G° - H2 98 )/T tt "298 AHf° AGf° OO -4.792 -233.132 -233.132 OO 100 14.408 14.516 54.396 -3.988 -234.506 -224.468 490.568 200 20.356 26.492 37.632 -2.228 -236.331 -215.397 235.372 298.15 24.667 35.490 35.490 -235.225 -203.841 149.417 300 24.717 35.636 35.489 .044 -235.226 -203.645 148.353 400 25.867 42.733 36.443 2.516 -235.216 -193.116 105.512 500 28.388 48.772 38.318 5.227 -235.045 -182.608 79.817 600 31.033 54.180 40.518 8.197 -234.702 -172.151 62.705 600.65 31.051 54.214 40.533 8.217 -234.699 -172.082 62.612 600.65 31.051 54.214 40.533 8.217 -235.846 -172.081 62.612 700 33.735 59.167 42.831 11.435 -235.324 -161.574 50.445 800 36.469 63.849 45.168 14.945 -234.570 -151.086 41.274 900 39.220 68.304 47.493 18.730 -233.564 -140.707 34.168 1,000 41.983 72.579 49.789 22.790 -232.308 -130.459 28.511 1,100 44.753 76.710 52.049 27.127 -230.796 -120.350 23.911 Phase changes: 600.65 K, melting point of Pb; AH° = 1.147 kcal/mol. Sources: The enthalpy of formation and entropy at 298 K are from CODATA (_7 ) . Low-temperature heat capacity values are from Gallagher (21) , while high-temperature enthalpy values are from Krestovnikov (35). 50 [Formation: Rb 2 S0 4 (c) Rubidium sulfate 2Rb(c,l) + S(c,l) + 2 2 (g) = Rb 2 S0 4 (c) T, K cal/(mol«K) kcal/mol Log Kf Cp° S° -(G° - H$ 98 )/T TjO TjO AHf° AGf° 298.15 32.011 47.190 47.190 -343.120 -314.742 230.709 300 32.087 47.388 47.191 .059 -343.125 -314.566 229.158 312.64 32.539 48.722 47.226 .467 -343.156 -313.362 219.051 312.64 32.539 48.722 47.226 .467 -344.204 -313.362 219.051 368.3 34.529 54.238 47.873 2.344 -344.331 -307.855 182.679 368.3 34.529 54.238 47.873 2.344 -344.427 -307.855 182.680 388.36 35.247 56.089 48.250 3.044 -344.452 -305.862 172.122 388.36 35.247 56.089 48.250 3.044 -344.865 -305.862 172.122 400 35.663 57.136 48.494 3.457 -344.891 -304.693 166.474 432.02 36.610 59.919 49.239 4.614 -344.960 -301.473 152.507 500 38.619 65.405 51.069 7.168 -345.115 -294.617 128.775 600 41.692 72.719 54.079 11.184 -344.940 -284.527 103.637 700 45.230 79.394 57.224 15.519 -344.391 -274.495 85.700 717.82 46.496 80.547 57.789 16.336 -344.243 -272.717 83.031 Phase changes : 312.64 K, melting point of Rb; AH° = 0.524 kcal/mol. 368.3 K, orthorhombic-monoclinic transformation of S; AH = 0.096 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation at 298 K is from CODATA (_7). The entropy at 298 K was calculated by Paukov (52) . Low-temperature heat capacities are from Paukov (52). High-temper- ature enthalpies are from Denielou (13). See text for high-temperature discussion. 51 [Formation: Rb 2 S0 4 (c,l) Rubidium sulfate 2Rb(c,l,g) + 0.5S 2 (g) + 2 2 (g) = Rb 2 S0 4 (c,l)] T, K cal/(mo] ■ •K) kcal/mol Log Kf Cp° S° -(G° - H! 98 )/T H° - H 2 9 8 AHf° AGf° 298.15 32.011 47.190 47.190 -358.475 -324.255 237.683 300 32.087 47.388 47.191 .059 -358.477 -324.043 236.062 312.64 32.539 48.722 47.226 .467 -358.488 -322.592 225.504 312.64 32.539 48.722 47.226 .467 -359.536 -322.592 225.504 400 35.663 57.136 48.494 3.457 -359.542 -312.259 170.608 500 38.619 65.405 51.069 7.168 -359.242 -300.470 131.334 600 41.692 72.719 54.079 11.184 -358.635 -288.768 105.182 700 45.230 79.394 57.224 15.519 -357.716 -277.190 86.541 800 52.335 85.828 60.397 20.345 -356.319 -265.774 72.605 900 69.840 92.855 63.602 26.328 -353.784 -254.577 61.819 931 78.971 95.367 64.616 28.629 -352.558 -251.180 58.963 931 43.881 95.479 64.616 28.733 -352.454 -251.180 58.963 974.5 45.053 97.509 66.040 30.667 -352.035 -246.465 55.274 974.5 45.053 97.509 66.040 30.667 -386.495 -246.465 55.274 1,000 45.740 98.682 66.857 31.825 -386.129 -242.806 53.065 1,100 48.435 103.168 69.955 36.534 -384.539 -228.547 45.408 1,200 51.129 107.498 72.905 41.512 -382.703 -214.446 39.056 1,300 53.824 111.697 75.729 46.759 -380.614 -200.507 33.708 1,339 54.874 113.303 76.799 48.879 -379.732 -195.116 31.846 1,339 49.335 120.203 76.799 58.059 -370.552 -195.116 31.846 1,400 49.335 122.401 78.780 61.069 -369.484 -187.210 29.224 1,500 49.335 125.805 81.804 66.002 -367.748 -174.253 25.388 1,600 49.335 128.989 84.655 70.935 -366.030 -161.411 22.047 1,700 49.335 131.980 87.351 75.869 -364.326 -148.673 19.113 1,800 49.335 134.800 89.910 80.802 -362.637 -136.034 16.517 1,900 49.335 137.467 92.343 85 736 -360.966 -123. 4 C - 14.205 2,000 49.335 139.998 94.664 90.66b -359.314 -111.039 12.134 Phase changes: 312.64 K, melting point of Rb; AH° = 0.524 kcal/mol. 931 K, transition for Rb 2 S0 4 ; AH° = 0.104 kcal/mol. 974.5 K, calculated boiling point of Rb fn ideal monatomic gas; AH e kcal/mol. 1,339 K, melting point of Rb 2 S0 4 ; 9.18 kcal/mol. = 17.230 Sources: The enthalpy of formation is from CODATA (7 ) . The entropy at 298 K was calculated by Paukov (52) . Low-temperature heat capacities are from Paukov (52) . High-temperature en- thalpies are from Denielou (13). See text for high-temperature discussion. 52 [Formation: Tl 2 S0 4 (c) Thallium sulfate 2Tl(c,l) + S(c,l) + 2 2 (g) = Tl 2 S0 4 (c)] T, K cal/(mol*K) kcal/mol Log Kf c P a S° -(G° - H^ 98 )/T ti. tt 298 AHf° AGf° 298.15 32.045 55.100 55.100 -322.800 -198.575 145.558 300 32.151 55.299 55.102 .059 -222.801 -198.425 144.551 368.3 35.664 62.263 55.794 2.383 -222.696 -192.884 114.456 368.3 35.664 62.263 55.794 2.383 -222.792 -192.884 114.456 388.36 36.695 64.182 56.179 3.108 -222.733 -191.257 107.628 388.36 36.695 64.182 56.179 3.108 -223.146 -191.257 107.628 400 37.294 65.275 56.428 3.539 -223.123 -190.301 103.975 432.02 38.753 68.203 57.193 4.757 -223.057 -187.677 94.941 500 41.852 74.092 59.094 7.499 -222.916 -182.113 79.600 507 42.155 74.676 59.305 7.793 -222.889 -181.541 78.255 507 42.155 74.676 59.305 7.793 -223.069 -181.541 78.255 577 45.185 80.322 61.516 10.851 -222.750 -175.822 66.595 577 45.185 80.322 61.516 10.851 -224.730 -175.822 66.595 600 46.181 82.108 62.271 11.902 -224.548 -173.879 63.335 700 50.400 89.544 65.641 16.732 -223.494 -165.503 51.672 717.82 51.143 90.820 66.250 17.637 -223.261 -164.029 49.940 Phase changes: 368.3 K, orthorhombic-monoclinic transformation of S; AH° = 0.906 kcal/mol. 388.36 K, melting point of S; AH° = 0.413 kcal/mol. 432.02 K, second-order transformation of S; AH° = kcal/mol. 507 K, ct-B transition point of Tl; AH° = 0.090 kcal/mol. 577 K, melting point of Tl; AH = 0.990 kcal/mol. 717.824 K, boiling point of S to equilibrium mixture of S n (n = 1 to 8). Sources: The enthalpy of formation after correction for the heat of formation of the sulfate ion and entropy at 298 K are from Wagman (63). High-temperature heat capacities are from Shmidt ( 57 ) and are matched with high-temperature enthalpy values of Dworkin (19). 53 [Formation: Tl 2 S0 4 (c,l) Thallium sulfate 2Tl(c,l) + 0.5S 2 (g) + 2 2 (g) = Tl 2 S0 4 (c,l)] T, K cal/(mol«K) kcal/mol Log Kf Cp° S° -' % 4 A •& • a v *^ 4& o *^ A w ^v 'W %.A O « ' .0 y« t v A v -V . <^ v o " o ,