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A8: van der Waal's Constants for Real Gases

  • Page ID
    15729
  • The van der Waal's equation of state for a non-ideal (real) gas is:

    \[ \left(P + \dfrac{an^2}{V^2}\right) (V − nb)=nRT \]

    • To convert \(a\) into atm L2/mol2 multiply by 0.986 atm/bar
    • To convert \(a\) into kPa L2/mol2 multiply by 100.0 kPa/bar
     
    Molecular Formula Name \(a\)
    bar L2/mol2
    \(b\)
    L/mol
    AlCl3 Aluminum trichloride 42.63 0.2450
    NH3 Ammonia 4.225 0.03713
    NH4Cl Ammonium chloride 2.380 0.00734
    Ar Argon 1.355 0.03201
    BCl3 Boron trichloride 15.60 0.1222
    BF3 Boron trifluoride 3.98 0.05443
    B2H6 Diborane 6.048 0.07437
    Br2 Bromine 9.75 0.0591
    ClFO2 Perchloryl fluoride 7.371 0.07130
    ClF5 Chlorine pentafluoride 9.58 0.08204
    ClH4P Phosphonium chloride 4.111 0.04545
    Cl2 Chlorine 6.343 0.05422
    Cl3FSi Trichlorofluorosilane 15.67 0.1273
    F2 Fluorine 1.171 0.02896
    GeCl4 Germanium tetrachloride 23.12 0.1489
    F3N Nitrogen trifluoride 3.58 0.05453
    F3P Phosphorus trifluoride 4.954 0.06510
    F4N2 Tetrafluorohydrazine 7.426 0.08564
    GeH4 Germane 5.743 0.06555
    He Helium 0.0346 0.0238
    HBr Hydrogen bromide 4.500 0.04415
    HCl Hydrogen chloride 3.700 0.04061
    HCN Hydrogen cyanide 11.29 0.08806
    HF Hydrogen fluoride 9.565 0.0739
    HI Hydrogen iodide 6.309 0.05303
    H2 Hydrogen 0.2453 0.02651
    H2O Water 5.537 0.03049
    H2S Hydrogen sulphide 4.544 0.04339
    H2Se Hydrogen selenide 5.523 0.0479
    Kr Krypton 2.325 0.0396
    SiH4 Silane 4.38 0.0579
    SiCl4 Silicon tetrachloride 20.96 0.1470
    SiF4 Silicon tetrafluoride 5.259 0.07236
    TiCl4 Titanium(IV) chloride 25.47 0.1423
    Hg Mercury 5.193 0.01057
    NO Nitric oxide 1.46 0.0289
    NO2 Nitrogen dioxide 5.36 0.0443
    N2 Nitrogen 1.370 0.0387
    N2O Nitrous oxide 3.852 0.04435
    N2H4 Hydrazine 8.46 0.0462
    Ne Neon 0.208 0.01672
    O2 Oxygen 1.382 0.03186
    O3 Ozone 3.570 0.0487
    P Phosphorus 53.6 0.157
    PH3 Phosphine 4.696 0.05157
    Rn Radon 6.601 0.06239
    SnCl4 Stannic chloride 27.25 0.1641
    S Sulphur 24.3 0.0660
    SO2 Sulphur dioxide 6.865 0.05679
    SF6 Sulphur hexafluoride 7.857 0.08786
    Se Selenium 33.4 0.0675
    UF6 Uranium(VI) fluoride 16.01 0.1128
    WF6 Tungsten(VI) fluoride 13.25 0.1063
    Xe Xenon 4.192 0.05156
    XeF2 Xenon difluoride 12.46 0.07037
    XeF4 Xenon tetrafluoride 15.52 0.09035
    CClF3 Chlorotrifluoromethane 6.873 0.08110
    CCl3F Trichlorofluoromethane 14.68 0.1111
    CCl4 Tetrachloromethane 20.01 0.1281
    CF4 Tetrafluoromethane 4.040 0.06325
    CO Carbon monoxide 1.472 0.03948
    COS Carbon oxysulphide 6.975 0.06628
    CO2 Carbon dioxide 3.658 0.04286
    CS2 Carbon disulphide 11.25 0.07262
    CHCl3 Trichloromethane 15.34 0.1019
    CHF3 Trifluoromethane 5.378 0.06403
    CH2Cl2 Dichloromethane 12.44 0.08689
    CH2F2 Difluoromethane 6.184 0.06268
    CH3Cl Chloromethane 7.566 0.06477
    CH3F Fluoromethane 5.009 0.05617
    NH3NO2 Nitromethane 17.18 0.1041
    CH4 Methane 2.300 0.04301
    CH3OH Methanol 9.472 0.06584
    CH3SH Methanethiol 8.911 0.06756
    CH3NH2 Methylamine 7.106 0.05879
    C2Cl2F3 1,1,2-Trichlorotrifluoroethane 20.25 0.1481
    C2F4 Tetrafluoroethylene 6.954 0.08085
    C2N2 Cyanogen 7.803 0.6952
    C2H2 Acetylene 4.516 0.05220
    C2H2F2 1,1-Difluoroethylene 6.000 0.07058
    C2H3Cl3 1,1,1-Trichloroethane 20.15 0.1317
    C2H3F Fluroethylene 5.984 0.06504
    C2H3F3 1,1,1-Trifluoroethane 9.302 0.09572
    C2H3N Acetonitrile 17.89 0.1169
    C2H4 Ethylene 4.612 0.05821
    C2H4Cl2 1,1-Dichloroethane 15.73 0.1072
    C2H4Cl2 1,2-Dichloroethane 17.0 0.108
    C2H4O Ethylene oxide 8.922 0.06779
    CH3COOH Acetic acid 17.71 0.1065
    C2H4O2 Methyl formate 11.54 0.08442
    C2H5Br Bromoethane 11.89 0.08406
    C2H5Cl Chloroethane 11.7 0.090
    C2H5F Fluoroethane 8.170 0.07758
    C2H6 Ethane 5.570 0.06499
    C2H6O Dimethyl ether 8.690 0.07742
    C2H5OH Ethanol 12.56 0.08710
    C2H5SH Dimethyl sulphide 13.34 0.09453
    C2H5SH Ethanethiol 13.23 0.09447
    C2H7N Dimethylamine 10.44 0.08510
    C2H7N Ethylamine 10.79 0.08433
    C3F8 Perfluoropropane 12.96 0.1338
    C3H5N Propanenitrile 21.57 0.1369
    C3H6 Propene 8.438 0.08242
    C3H6 Cyclopropane 8.293 0.07420
    C3H6O Acetone 16.02 0.1124
    C3H6O Propanal 14.08 0.09947
    C3H6O2 Ethyl formate 15.91 0.1115
    C3H6O2 Methyl acetate 15.75 0.1108
    C3H6O2 Propanoic acid 23.49 0.1386
    C3H7Cl 1-Chloropropane 16.11 0.1141`
    C3H8 Propane 9.385 0.09044
    C3H8O 1-Propanol 16.26 0.1080
    C3H8O 2-Propanol 15.82 0.1109
    C3H8O Ethyl methyl ether 12.70 0.1034
    C3H8S Ethyl methyl sulphide 19.45 0.1300
    C3H9N Propylamine 15.26 0.1094
    C3H9N Trimethylamine 13.37 0.1101
    C4H4O Furan 12.74 0.0926
    C4H4S Thiophene 17.21 0.1058
    C4H4N Pyrrole 18.82 0.1049
    C4H6 1,3-Butadiene 12.17 0.1020
    C4H6O3 Acetic anhydride 26.8 0.157
    C4H7N Butanenitrile 25.76 0.1568
    C4H8 1-Butene 12.76 0.1084
    C4H8 Cyclobutane 12.39 0.0960
    C4H8O 2-Butanone 19.97 0.1326
    C4H8O Tetrahydrofuran 16.39 0.1082
    C4H8O2 1,4-Dioxane 19.29 0.1171
    C4H8O2 Ethyl acetate 20.57 0.1401
    C4H8O2 Methyl propanoate 20.51 0.1377
    C4H8O2 Propyl formate 20.79 0.1377
    C4H8O2 Butanoic acid 28.18 0.1609
    C4H9N Pyrrolidine 16.84 0.1056
    C4H10 Butane 13.93 0.1168
    C4H10 Isobutane 13.36 0.1168
    C4H10O 1-Butanol 20.90 0.1323
    C4H10O 2-Methyl-2-propanol 18.81 0.1324
    C4H10O 2-Methyl-1-propanol 20.35 0.1324
    C4H10O Diethyl ether 17.46 0.1333
    C4H10S Diethyl sulphide 22.85 0.1462
    C4H11N Butylamine 19.41 0.1301
    C4H11N Diethylamine 19.40 0.1383
    C4H12Si Tetramethylsilane 20.81 0.1653
    C5H4O2 Furfural 22.23 0.1182
    C5H5N Pyridine 19.77 0.1137
    C5H8 Cyclopentene 15.61 0.1097
    C5H10 1-Pentene 17.86 0.1370
    C5H10 2-Methyl-1-butene 16.9 0.129
    C5H10 2-Methyl-2-butene 17.26 0.1279
    C5H10 Cyclopentane 16.94 0.1180
    C5H10O Tetrahydropyran 20.02 0.1247
    C5H10O2 Isobutyl formate 22.82 0.1476
    C5H10O2 Propyl acetate 26.23 0.1700
    C5H10O2 Ethyl propanoate 25.86 0.1688
    C5H10O2 Methyl butanoate 25.83 0.1661
    C5H10O2 Methyl isobutanoate 24.87 0.1639
    C5H11N Piperidine 20.84 0.1250
    C5H12 Pentane 19.13 0.1451
    C5H12 Isopentane 18.29 0.1415
    C5H12 Neopentane 17.17 0.1410
    C5H12O 1-Pentanol 25.81 0.1564
    C6H5Br Bromobenzene 28.96 0.1541
    C6H5Cl Chlorobenzene 25.80 0.1454
    C6H5F Fluorobenzene 20.10 0.1279
    C6H5I Iodobenzene 33.54 0.1658
    C6H6 Benzene 18.82 0.1193
    C6H5OH Phenol 22.93 0.1177
    C6H5NH2 Aniline 29.14 0.1486
    C6H10O Cyclohexanone 31.1 0.170
    C6H11N Hexanenitrile 35.50 0.1996
    C6H12 Cyclohexane 21.95 0.1413
    C6H11OH Cyclohexanol 28.93 0.1586
    C6H12O2 Pentyl formate 27.97 0.1730
    C6H12O2 Isobutyl acetate 29.05 0.1845
    C6H12O2 Ethyl butanoate 30.53 0.1922
    C6H12O2 Ethyl 2-methylpropanoate 29.05 0.1872
    C6H12O2 Methyl pentanoate 29.39 0.1847
    C6H14 Hexane 24.97 0.1753
    C6H14 2,3-Dimethylbutane 23.29 0.1660
    C6H14O 1-Hexanol 31.35 0.1829
    C6H15N Triethylamine 27.59 0.1836
    C6H15N Dipropylamine 24.82 0.1591
    C7H5N Benzonitrile 33.89 0.1727
    C7H6O Benzaldehyde 30.30 0.1553
    C7H8 Toluene 24.89 0.1499
    C7H8O o-Cresol 28.33 0.1447
    C7H8O m-Cresol 31.86 0.1609
    C7H8O p-Cresol 28.11 0.1422
    C7H8O Benzyl alcohol 34.7 0.173
    C7H8O Anisole 28.60 0.1579
    C7H16 Heptane 30.89 0.2038
    C7H15OH Heptanol 37.22 0.2097
    C8H10 Ethylbenzene 30.86 0.1782
    C8H10 o-Xylene 31.06 0.1756
    C8H10 m-Xylene 31.41 0.1814
    C8H10 p-Xylene 31.54 0.1824
    C8H10O Phenetole 35.70 0.1966
    C8H11N N,N-Dimethylaniline 37.92 0.1967
    C8H18 Octane 37.86 0.2372
    C8H18 2,5-Dimethylhexane 35.49 0.2299
    C8H18O 1-Octanol 43.42 0.2371
    C9H7N Quinoline 36.70 0.1672
    C9H12 Cumene 36.20 0.2044
    C9H12 Propylbenzene 37.14 0.2073
    C9H12 1,2,4-Trimethylbenzene 38.03 0.2088
    C9H12 Mesitylene 37.87 0.2118
    C9H20 Nonane 45.11 0.2702
    C9H20O 1-Nonanol 50.00 0.2654
    C10H8 Naphthalene 40.32 0.1920
    C10H14 Butylbenzene 44.07 0.2378
    C10H14 Isobutylbenzene 40.40 0.2215
    C10H14 o-Cymene 42.7 0.234
    C10H14 p-Cymene 45.27 0.2478
    C10H14 p-Diethylbenzene 45.03 0.2439
    C10H14 1,2,4,5-Tetramethylbenzene 45.8 0.24
    C10H22 Decane 52.88 0.3051
    C10H22O 1-Decanol 57.45 0.2971
    C11H24 Undecane 60.88 0.3396
    C12H10 Biphenyl 47.16 0.2130
    C12H26 Dodecane 69.14 0.3741
    C12H26O 1-Dodecanol 72.69 0.3598
    C13H12 Diphenylmethane 60.46 0.2798
    C13H28 Tridecane 77.94 0.4109
    C13H28O 1-Tridecanol 81.20 0.3942
    C14H30O 1-Tetradecanol 89.91 0.4289
    C15H32 Pentadecane 96.50 0.4857