Van der Waals constants (data page)

The following table lists the Van der Waals constants (from the Van der Waals equation) for a number of common gases and volatile liquids.^[1] These constants are generally calculated from the critical pressure ${\displaystyle p_{c}}$ and temperature ${\displaystyle T_{c}}$ using the formulas ${\displaystyle a={\frac {27}{64}}{\frac {R^{2}T_{c}^{2}}{p_{c}}}}$ and ${\displaystyle b={\frac {RT_{c}}{8p_{c}}}}$.

To convert from ${\displaystyle \mathrm {L^{2}bar/mol^{2}} }$ to ${\displaystyle \mathrm {L^{2}kPa/mol^{2}} }$, multiply by 100.
To convert from ${\displaystyle \mathrm {L^{2}bar/mol^{2}} }$ to ${\displaystyle \mathrm {m^{6}Pa/mol^{2}} }$, divide by 10.
To convert from ${\displaystyle \mathrm {L/mol} }$ to ${\displaystyle \mathrm {m^{3}/mol} }$, divide by 1000.

	a (L2bar/mol2)	b (L/mol)
Acetic acid	17.7098	0.1065
Acetic anhydride	20.158	0.1263
Acetone	16.02	0.1124
Acetonitrile	17.81	0.1168
Acetylene	4.516	0.0522
Ammonia	4.225	0.0371
Aniline[2]	29.14	0.1486
Argon	1.355	0.03201
Benzene	18.24	0.1193
Bromobenzene	28.94	0.1539
Butane	14.66	0.1226
1-Butanol[2]	20.94	0.1326
2-Butanone[2]	19.97	0.1326
Carbon dioxide	3.6	0.04267
Carbon disulfide	11.77	0.07685
Carbon monoxide	1.505	0.0398500
Carbon tetrachloride	19.7483	0.1281
Chlorine	6.579	0.05622
Chlorobenzene	25.77	0.1453
Chloroethane	11.05	0.08651
Chloromethane	7.570	0.06483
Cyanogen	7.769	0.06901
Cyclohexane	23.11	0.1424
Cyclopropane[2]	8.34	0.0747
Decane[2]	52.74	0.3043
1-Decanol[2]	59.51	0.3086
Diethyl ether	17.61	0.1344
Diethyl sulfide	19.00	0.1214
Dimethyl ether	8.180	0.07246
Dimethyl sulfide	13.04	0.09213
Dodecane[2]	69.38	0.3758
1-Dodecanol[2]	75.70	0.3750
Ethane	5.562	0.0638
Ethanethiol	11.39	0.08098
Ethanol	12.18	0.08407
Ethyl acetate	20.72	0.1412
Ethylamine	10.74	0.08409
Ethylene[2]	4.612	0.0582
Fluorine[2]	1.171	0.0290
Fluorobenzene	20.19	0.1286
Fluoromethane	4.692	0.05264
Freon	10.78	0.0998
Furan[2]	12.74	0.0926
Germanium tetrachloride	22.90	0.1485
Helium	0.0346	0.0238
Heptane[2]	31.06	0.2049
1-Heptanol[2]	38.17	0.2150
Hexane	24.71	0.1735
1-Hexanol[2]	31.79	0.1856
Hydrazine[2]	8.46	0.0462
Hydrogen	0.2476	0.02661
Hydrogen bromide	4.510	0.04431
Hydrogen chloride	3.716	0.04081
Hydrogen cyanide[2]	11.29	0.0881
Hydrogen fluoride[2]	9.565	0.0739
Hydrogen iodide[2]	6.309	0.0530
Hydrogen selenide	5.338	0.04637
Hydrogen sulfide	4.490	0.04287
Isobutane[2]	13.32	0.1164
Iodobenzene	33.52	0.1656
Krypton	2.349	0.03978
Mercury	8.200	0.01696
Methane	2.253	0.04278
Methanol	9.649	0.06702
Methylamine[2]	7.106	0.0588
Neon	0.2135	0.01709
Neopentane[2]	17.17	0.1411
Nitric oxide	1.358	0.02789
Nitrogen	1.370	0.0387
Nitrogen dioxide	5.354	0.04424
Nitrogen trifluoride[2]	3.58	0.0545
Nitrous oxide	3.832	0.04415
Octane[2]	37.88	0.2374
1-Octanol[2]	44.71	0.2442
Oxygen	1.382	0.03186
Ozone[2]	3.570	0.0487
Pentane	19.26	0.146
1-Pentanol[2]	25.88	0.1568
Phenol[2]	22.93	0.1177
Phosphine	4.692	0.05156
Propane	8.779	0.08445
1-Propanol[2]	16.26	0.1079
2-Propanol[2]	15.82	0.1109
Propene[2]	8.442	0.0824
Pyridine[2]	19.77	0.1137
Pyrrole[2]	18.82	0.1049
Radon	6.601	0.06239
Silane	4.377	0.05786
Silicon tetrafluoride	4.251	0.05571
Sulfur dioxide	6.803	0.05636
Sulfur hexafluoride[2]	7.857	0.0879
Tetrachloromethane[2]	20.01	0.1281
Tetrachlorosilane[2]	20.96	0.1470
Tetrafluoroethylene[2]	6.954	0.0809
Tetrafluoromethane[2]	4.040	0.0633
Tetrafluorosilane[2]	5.259	0.0724
Tetrahydrofuran[2]	16.39	0.1082
Tin tetrachloride	27.27	0.1642
Thiophene[2]	17.21	0.1058
Toluene	24.38	0.1463
1-1-1-Trichloroethane[2]	20.15	0.1317
Trichloromethane[2]	15.34	0.1019
Trifluoromethane[2]	5.378	0.0640
Trimethylamine[2]	13.37	0.1101
Water	5.536	0.03049
Xenon	4.250	0.05105

Units

1 J·m³/mol² = 1 m⁶·Pa/mol² = 10 L²·bar/mol²

1 L²atm/mol² = 0.101325 J·m³/mol² = 0.101325 Pa·m⁶/mol²

1 dm³/mol = 1 L/mol = 1 m³/kmol = 0.001 m³/mol (where kmol is kilomoles = 1000 moles)