CODATA KEY VALUES FOR THERMODYNAMICS

The Committee on Data for Science and Technology (CODATA) has conducted a project to establish internationally agreed values for the thermodynamic properties of key chemical substances. This table presents the final results of the project. Use of these recommended, internally consistent values is encouraged in the analysis of thermodynamic measurements, data reduction, and preparation of other thermodynamic tables. The table includes the standard enthalpy of formation at 298.15 K, the entropy at 298.15 K, and the quantity H ° (298.15 K)-H °(0). A value of 0 in the DfH ° column for an element indicates the reference state for that element. The standard state pressure is 100000 Pa (1 bar). See the reference for information on the dependence of gas-phase entropy on the choice of standard state pressure. Substances are listed in alphabetical order of their chemical formulas when written in the most common form.

REFERENCE

Cox, J. D., Wagman, D. D., and Medvedev, V. A., CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1989.

The values given in this table represent the consensus judgement of an international group of experts. While we believe there is a high probability that the true values fall within the stated uncertainty limits, CODATA cannot assume responsibility for any consequences of the use of these data.

(Note: All the numerical values have precisions stated alongside them. Browsers using HTML3.2 will show a +- symbol.Earlier versions will only show a space or possibly some code)

Substance State DfH ° (298.15 K) S ° (298.15 K) H ° (298.15 K)-H ° (0)
kJ mol-1 J K-1 mol-1 kJ mol-1
Ag cr 0 42.55 ± 0.20 5.745 ± 0.020
Ag g 284.9 ± 0.8 172.997 ± 0.004 6.197 ± 0.001
Ag+ aq 105.79 ± 0.08 73.45 ± 0.40
AgCl cr -127.01 ± 0.05 96.25 ± 0.20 12.033 ± 0.020
Al cr 0 28.30 ± 0.10 4.540 ± 0.020
Al g 330.0 ± 4.0 164.554 ± 0.004 6.919 ± 0.001
Al+3 aq -538.4 ± 1.5 -325 ± 10
AlF3 cr -1510.4 ± 1.3 66.5 ± 0.5 11.62 ± 0.04
Al2O3 cr,corundum -1675.7 ± 1.3 50.92 ± 0.10 10.016 ± 0.020
Ar g 0 154.846 ± 0.003 6.197 ± 0.001
B cr,rhombic 0 5.90 ± 0.08 1.222 ± 0.008
B g 565 ± 5 153.436 ± 0.015 6.316 ± 0.002
BF3 g -1136.0 ± 0.8 254.42 ± 0.20 11.650 ± 0.020
B2O3 cr -1273.5 ± 1.4 53.97 ± 0.30 9.301 ± 0.040
Be cr 0 9.50 ± 0.08 1.950 ± 0.020
Be g 324 ± 5 136.275 ± 0.003 6.197 ± 0.001
BeO cr -609.4 ± 2.5 13.77 ± 0.04 2.837 ± 0.008
Br g 111.87 ± 0.12 175.018 ± 0.004 6.197 ± 0.001
Br- aq -121.41 ± 0.15 82.55 ± 0.20
Br2 l 0 152.21 ± 0.30 24.52 ± 0.01
Br2 g 30.91 ± 0.11 245.468 ± 0.005 9.725 ± 0.001
C cr,graphite 0 5.74 ± 0.10 1.050 ± 0.020
C g 716.68 ± 0.45 158.100 ± 0.003 6.536 ± 0.001
CO g -110.53 ± 0.17 197.660 ± 0.004 8.671 ± 0.001
CO2 g -393.51 ± 0.13 213.785 ± 0.010 9.365 ± 0.003
CO2 aq,undissoc. -413.26 ± 0.20 119.36 ± 0.60
CO3-2 aq -675.23 ± 0.25 -50.0 ± 1.0
Ca cr 0 41.59 ± 0.40 5.736 ± 0.040
Ca g 177.8 ± 0.8 154.887 ± 0.004 6.197 ± 0.001
Ca+2 aq -543.0 ± 1.0 -56.2 ± 1.0
CaO cr -634.92 ± 0.90 38.1 ± 0.4 6.75 ± 0.06
Cd cr 0 51.80 ± 0.15 6.247 ± 0.015
Cd g 111.80 ± 0.20 167.749 ± 0.004 6.197 ± 0.001
Cd+2 aq -75.92 ± 0.60 -72.8 ± 1.5
CdO cr -258.35 ± 0.40 54.8 ± 1.5 8.41 ± 0.08
CdSO4 8/3H2O cr -1729.30 ± 0.80 229.65 ± 0.40 35.56 ± 0.04
Cl g 121.301 ± 0.008 165.190 ± 0.004 6.272 ± 0.001
Cl- aq -167.080 ± 0.10 56.60 ± 0.20
ClO4- aq -128.10 ± 0.40 184.0 ± 1.5
Cl2 g 0 223.081 ± 0.010 9.181 ± 0.001
Cs cr 0 85.23 ± 0.40 7.711 ± 0.020
Cs g 76.5 ± 1.0 175.601 ± 0.003 6.197 ± 0.001
Cs+ aq -258.00 ± 0.50 132.1 ± 0.5
Cu cr 0 33.15 ± 0.08 5.004 ± 0.008
Cu g 337.4 ± 1.2 166.398 ± 0.004 6.197 ± 0.001
Cu+2 aq 64.9 ± 1.0 -98 ± 4
CuSO4 cr -771.4 ± 1.2 109.2 ± 0.4 16.86 ± 0.08
F g 79.38 ± 0.30 158.751 ± 0.004 6.518 ± 0.001
F- aq -335.35 ± 0.65 -13.8 ± 0.8
F2 g 0 202.791 ± 0.005 8.825 ± 0.001
Ge cr 0 31.09 ± 0.15 4.636 ± 0.020
Ge g 372 ± 3 167.904 ± 0.005 7.398 ± 0.001
GeF4 g -1190.20 ± 0.50 301.9 ± 1.0 17.29 ± 0.10
GeO2 cr,tetragonal -580.0 ± 1.0 39.71 ± 0.15 7.230 ± 0.020
H g 217.998 ± 0.006 114.717 ± 0.002 6.197 ± 0.001
H+ aq 0 0
HBr g -36.29 ± 0.16 198.700 ± 0.004 8.648 ± 0.001
HCO3- aq -689.93 ± 2.0 98.4 ± 0.5
HCl g -92.31 ± 0.10 186.902 ± 0.005 8.640 ± 0.001
HF g -273.30 ± 0.70 173.779 ± 0.003 8.599 ± 0.001
HI g 26.50 ± 0.10 206.590 ± 0.004 8.657 ± 0.001
HPO4-2 aq -1299.0 ± 1.5 -33.5 ± 1.5
HS- aq -16.3 ± 1.5 67 ± 5
HSO4- aq -886.9 ± 1.0 131.7 ± 3.0
H2 g 0 130.680 ± 0.003 8.468 ± 0.001
H2O l -285.830 ± 0.040 69.95 ± 0.03 13.273 ± 0.020
H2O g -241.826 ± 0.040 188.835 ± 0.010 9.905 ± 0.005
H2PO4- aq -1302.6 ± 1.5 92.5 ± 1.5
H2S g -20.6 ± 0.5 205.81 ± 0.05 9.957 ± 0.010
H2S aq,undissoc. -38.6 ± 1.5 126 ± 5
H3BO3 cr -1094.8 ± 0.8 89.95 ± 0.60 13.52 ± 0.04
H3BO3 aq,undissoc. -1072.8 ± 0.8 162.4 ± 0.6
He g 0 126.153 ± 0.002 6.197 ± 0.001
Hg l 0 75.90 ± 0.12 9.342 ± 0.008
Hg g 61.38 ± 0.04 174.971 ± 0.005 6.197 ± 0.001
Hg+2 aq 170.21 ± 0.20 -36.19 ± 0.80
HgO cr,red -90.79 ± 0.12 70.25 ± 0.30 9.117 ± 0.025
Hg2+2 aq 166.87 ± 0.50 65.74 ± 0.80
Hg2Cl2 cr -265.37 ± 0.40 191.6 ± 0.8 23.35 ± 0.20
Hg2SO4 cr -743.09 ± 0.40 200.70 ± 0.20 26.070 ± 0.030
I g 106.76 ± 0.04 180.787 ± 0.004 6.197 ± 0.001
I- aq -56.78 ± 0.05 106.45 ± 0.30
I2 cr 0 116.14 ± 0.30 13.196 ± 0.040
I2 g 62.42 ± 0.08 260.687 ± 0.005 10.116 ± 0.001
K cr 0 64.68 ± 0.20 7.088 ± 0.020
K g 89.0 ± 0.8 160.341 ± 0.003 6.197 ± 0.001
K+ aq -252.14 ± 0.08 101.20 ± 0.20
Kr g 0 164.085 ± 0.003 6.197 ± 0.001
Li cr 0 29.12 ± 0.20 4.632 ± 0.040
Li g 159.3 ± 1.0 138.782 ± 0.010 6.197 ± 0.001
Li+ aq -278.47 ± 0.08 12.24 ± 0.15
Mg cr 0 32.67 ± 0.10 4.998 ± 0.030
Mg g 147.1 ± 0.8 148.648 ± 0.003 6.197 ± 0.001
Mg+2 aq -467.0 ± 0.6 -137 ± 4
MgF2 cr -1124.2 ± 1.2 57.2 ± 0.5 9.91 ± 0.06
MgO cr -601.60 ± 0.30 26.95 ± 0.15 5.160 ± 0.020
N g 472.68 ± 0.40 153.301 ± 0.003 6.197 ± 0.001
NH3 g -45.94 ± 0.35 192.77 ± 0.05 10.043 ± 0.010
NH4+ aq -133.26 ± 0.25 111.17 ± 0.40
NO3- aq -206.85 ± 0.40 146.70 ± 0.40
N2 g 0 191.609 ± 0.004 8.670 ± 0.001
Na cr 0 51.30 ± 0.20 6.460 ± 0.020
Na g 107.5 ± 0.7 153.718 ± 0.003 6.197 ± 0.001
Na+ aq -240.34 ± 0.06 58.45 ± 0.15
Ne g 0 146.328 ± 0.003 6.197 ± 0.001
O g 249.18 ± 0.10 161.059 ± 0.003 6.725 ± 0.001
OH- aq -230.015 ± 0.040 -10.90 ± 0.20
O2 g 0 205.152 ± 0.005 8.680 ± 0.002
P cr,white 0 41.09 ± 0.25 5.360 ± 0.015
P g 316.5 ± 1.0 163.199 ± 0.003 6.197 ± 0.001
P2 g 144.0 ± 2.0 218.123 ± 0.004 8.904 ± 0.001
P4 g 58.9 ± 0.3 280.01 ± 0.50 14.10 ± 0.20
Pb cr 0 64.80 ± 0.30 6.870 ± 0.030
Pb g 195.2 ± 0.8 175.375 ± 0.005 6.197 ± 0.001
Pb+2 aq 0.92 ± 0.25 18.5 ± 1.0
PbSO4 cr -919.97 ± 0.40 148.50 ± 0.60 20.050 ± 0.040
Rb cr 0 76.78 ± 0.30 7.489 ± 0.020
Rb g 80.9 ± 0.8 170.094 ± 0.003 6.197 ± 0.001
Rb+ aq -251.12 ± 0.10 121.75 ± 0.25
S cr,rhombic 0 32.054 ± 0.050 4.412 ± 0.006
S g 277.17 ± 0.15 167.829 ± 0.006 6.657 ± 0.001
SO2 g -296.81 ± 0.20 248.223 ± 0.050 10.549 ± 0.010
SO4-2 aq -909.34 ± 0.40 18.50 ± 0.40
S2 g 128.60 ± 0.30 228.167 ± 0.010 9.132 ± 0.002
Si cr 0 18.81 ± 0.08 3.217 ± 0.008
Si g 450 ± 8 167.981 ± 0.004 7.550 ± 0.001
SiF4 g -1615.0 ± 0.8 282.76 ± 0.50 15.36 ± 0.05
SiO2 cr,alpha quartz -910.7 ± 1.0 41.46 ± 0.20 6.916 ± 0.020
Sn cr,white 0 51.18 ± 0.08 6.323 ± 0.008
Sn g 301.2 ± 1.5 168.492 ± 0.004 6.215 ± 0.001
Sn+2 aq -8.9 ± 1.0 -16.7 ± 4.0
SnO cr,tetragonal -280.71 ± 0.20 57.17 ± 0.30 8.736 ± 0.020
SnO2 cr,tetragonal -577.63 ± 0.20 49.04 ± 0.10 8.384 ± 0.020
Th cr 0 51.8 ± 0.5 6.35 ± 0.05
Th g 602 ± 6 190.17 ± 0.05 6.197 ± 0.003
ThO2 cr -1226.4 ± 3.5 65.23 ± 0.20 10.560 ± 0.020
Ti cr 0 30.72 ± 0.10 4.824 ± 0.015
Ti g 473 ± 3 180.298 ± 0.010 7.539 ± 0.002
TiCl4 g -763.2 ± 3.0 353.2 ± 4.0 21.5 ± 0.5
TiO2 cr,rutile -944.0 ± 0.8 50.62 ± 0.30 8.68 ± 0.05
U cr 0 50.20 ± 0.20 6.364 ± 0.020
U g 533 ± 8 199.79 ± 0.10 6.499 ± 0.020
UO2 cr -1085.0 ± 1.0 77.03 ± 0.20 11.280 ± 0.020
UO2+2 aq -1019.0 ± 1.5 -98.2 ± 3.0
UO3 cr,gamma -1223.8 ± 1.2 96.11 ± 0.40 14.585 ± 0.050
U3O8 cr -3574.8 ± 2.5 282.55 ± 0.50 42.74 ± 0.10
Xe g 0 169.685 ± 0.003 6.197 ± 0.001
Zn cr 0 41.63 ± 0.15 5.657 ± 0.020
Zn g 130.40 ± 0.40 160.990 ± 0.004 6.197 ± 0.001
Zn+2 aq -153.39 ± 0.20 -109.8 ± 0.5
ZnO cr -350.46 ± 0.27 43.65 ± 0.40 6.933 ± 0.040