Molecular
Individual Gas Constant - R
Weight
Gas
Name
Formula
[g/mol], [J/kg
[kg/kmol] K]
Acetylene
C2H2
26.038
Air
[kcal/(kg
[kJ/kg [Wh/(kg K)],
[kcal/(lb
[Btu(IT)/lb °F)]
K]
K)]
°F]
[ft lbf/lb [ft lbf/slug
°R]
°R]
319.32 0.3193 0.08870
0.07627
0.0623
59.350
1910
A
28.9647
mixture
287.05 0.2871 0.07974
0.06856
0.0560
53.353
1717
Ammonia
NH3
17.031
488.21 0.4882 0.13561
0.11661
0.0952
90.740
2919
Argon
Ar
39.948
208.13 0.2081 0.05781
0.04971
0.0406
38.684
1245
Butane
C4H10
58.122
143.05 0.1431 0.03974
0.03417
0.0279
26.588
855
Butene
C4H8
56.106
148.19 0.1482 0.04116
0.03539
0.0289
27.543
886
Carbon Dioxide
CO2
44.010
188.92 0.1889 0.05248
0.04512
0.0368
35.114
1130
Carbon Monoxide
CO
28.010
296.84 0.2968 0.08246
0.07090
0.0579
55.171
1775
Carbonic acid
H2CO3
62.025
134.05 0.1341 0.03724
0.03202
0.0261
24.915
802
Chlorine
Cl2
70.906
117.26 0.1173 0.03257
0.02801
0.0229
21.794
701
Chloromethane
CH3Cl
50.488
164.68 0.1647 0.04575
0.03933
0.0321
30.608
985
Dichlorofluorumethane CHCl2F
102.923
80.78 0.0808 0.02244
0.01929
0.0158
15.015
483
Ethane
C2H6
30.069
276.51 0.2765 0.07681
0.06604
0.0539
51.393
1654
Ethene
C2H4
28.053
296.38 0.2964 0.08233
0.07079
0.0578
55.086
1772
Fluorine
F2
37.997
218.82 0.2188 0.06078
0.05226
0.0427
40.670
1309
Helium
He
4.003
2077.1 2.0771 0.57696
0.49610
0.4050
386.047 12421
Hydrogen
H2
2.016
4124.2 4.1242 1.14563
0.98506
0.8043
766.541 24663
Hydrogen bromide
HBr
80.912
102.76 0.1028 0.02854
0.02454
0.0200
19.099
614
Hydrogen chloride
HCl
36.461
228.04 0.2280 0.06334
0.05447
0.0445
42.384
1364
Molecular
Individual Gas Constant - R
Weight
Gas
[kcal/(kg
[kJ/kg [Wh/(kg K)],
[kcal/(lb
[Btu(IT)/lb °F)]
K]
K)]
°F]
Name
Formula
[g/mol], [J/kg
[kg/kmol] K]
[ft lbf/lb [ft lbf/slug
°R]
°R]
Hydrogen sulfide
H2S
34.081
243.96 0.2440 0.06777
0.05827
0.0476
45.344
1459
Krypton
Kr
83.798
99.22 0.0992 0.02756
0.02370
0.0193
18.441
593
Methane (natural gas) CH4
16.042
518.28 0.5183 0.14397
0.12379
0.1011
96.329
3099
Neon
Ne
20.180
412.02 0.4120 0.11445
0.09841
0.0803
76.579
2464
Nitrogen
N2
28.013
296.80 0.2968 0.08245
0.07089
0.0579
55.165
1775
Nitrogen dioxide
NO2
46.006
180.73 0.1807 0.05020
0.04317
0.0352
33.590
1081
Nitrogen trifluoride
NF3
71.002
117.10 0.1171 0.03253
0.02797
0.0228
21.765
700
Nitrous oxide
N2O
44.012
188.91 0.1889 0.05248
0.04512
0.0368
35.112
1130
Oxygen
O2
31.999
259.84 0.2598 0.07218
0.06206
0.0507
48.294
1554
Propane
C3H8
44.096
188.56 0.1886 0.05238
0.04504
0.0368
35.045
1128
Propene
C3H6
42.080
197.59 0.1976 0.05489
0.04719
0.0385
36.724
1182
Sulfur dioxide
SO2
64.064
129.78 0.1298 0.03605
0.03100
0.0253
24.122
776
Sulfur hexafluoride
SF6
146.055
56.93 0.0569 0.01581
0.01360
0.0111
10.581
340
Sulfur trioxide
SO3
80.063
103.85 0.1038 0.02885
0.02480
0.0203
19.302
621
Water vapor
H2O
18.015
461.52 0.4615 0.12820
0.11023
0.0900
85.780
2760
Xenon
Xe
131.293
63.33 0.0633 0.01759
0.01513
0.0123
11.770
379