Related Resources: thermodynamics
Properties Ideal Gases
Properties of Various Ideal Gases at 77 F°, 1 atm (English Units)
Gas |
Chemical
Formula |
Mol. Mass
(lbm/lbmol) |
R
(ft-lbf/lbm R) |
ρ × 103
(lbm/ft 3 ) |
Cρo
(Btu/lbm R) |
Cv0
|
k
Cρo / Cv0 |
Steam |
H2O
|
18.015
|
85.76
|
1.442
|
0.447
|
0.337
|
1.327
|
Acetylene |
C2 H 2
|
26.038
|
59.34
|
65.55
|
0.406
|
0.330
|
1.231
|
Air |
—
|
28.97
|
53.34
|
72.98
|
0.240
|
0.171
|
1.400
|
Ammonia |
NH3
|
17.031
|
90.72
|
43.325
|
0.509
|
0.392
|
1.297
|
Argon |
Ar
|
39.948
|
38.68
|
100.7
|
0.124
|
0.0745
|
1.667
|
Butane |
C4 H10
|
58.124
|
26.58
|
150.3
|
0.410
|
0.376
|
1.091
|
Carbon dioxide |
CO2
|
44.01
|
35.10
|
110.8
|
0.201
|
0.156
|
1.289
|
Carbon monoxide |
CO
|
28.01
|
55.16
|
70.5
|
0.249
|
0.178
|
1.399
|
Ethane |
C2 H6
|
30.07
|
51.38
|
76.29
|
0.422
|
0.356
|
1.186
|
Ethanol |
C2H 5OH
|
46.069
|
33.54
|
117.6
|
0.341
|
0.298
|
1.145
|
Ethylene |
C2 H4
|
28.054
|
55.07
|
71.04
|
0.370
|
0.299
|
1.237
|
Helium |
He
|
4.003
|
386.0
|
10.08
|
1.240
|
0.744
|
1.667
|
Hydrogen |
H 2
|
2.016
|
766.5
|
5.075
|
3.394
|
2.409
|
1.409
|
Methane |
CH 4
|
16.043
|
96.35
|
40.52
|
0.538
|
0.415
|
1.299
|
Methanol |
CH3OH
|
32.042
|
48.22
|
81.78
|
0.336
|
0.274
|
1.227
|
Neon |
Ne
|
20.183
|
76.55
|
50.81
|
0.246
|
0.148
|
1.667
|
Nitric oxide |
NO
|
30.006
|
51.50
|
75.54
|
0.237
|
0.171
|
1.387
|
Nitrogen |
N 2
|
28.013
|
55.15
|
70.61
|
0.249
|
0.178
|
1.400
|
Nitrous oxide |
N2O
|
44.013
|
35.10
|
110.8
|
0.210
|
0.165
|
1.274
|
n -octane |
C8H18
|
114.23
|
13.53
|
5.74
|
0.409
|
0.391
|
1.044
|
Oxygen |
O2
|
31.999
|
48.28
|
80.66
|
0.220
|
0.158
|
1.393
|
Propane |
C3H8
|
44.094
|
35.04
|
112.9
|
0.401
|
0.356
|
1.126
|
R-12 |
CCl2F2
|
120.914
|
12.78
|
310.9
|
0.147
|
0.131
|
1.126
|
R-22 |
CHClF2
|
86.469
|
17.87
|
221.0
|
0.157
|
0.134
|
1.171
|
R-32 |
CF2 H2
|
52.024
|
29.70
|
132.6
|
0.196
|
0.158
|
1.242
|
R-125 |
CHF2 CF3
|
120.022
|
12.87
|
307.0
|
0.189
|
0.172
|
1.097
|
R-134a |
CF3CH 2F
|
102.03
|
15.15
|
262.2
|
0.203
|
0.184
|
1.106
|
Sulfur dioxide |
SO2
|
64.059
|
24.12
|
163.4
|
0.149
|
0.118
|
1.263
|
Sulfur trioxide |
SO3
|
80.053
|
19.30
|
204.3
|
0.152
|
0.127
|
1.196
|
Or saturation pressure if it is less than 1 atm.