Density of Gases

Densities and molecular weights of common gases like acetylene, air, methane, nitrogen, oxygen and others.

GasFormulaMolecular WeightDensity (kg/m³) - NTPDensity (kg/m³) - STPDensity (lb/ft³) - NTPDensity (lb/ft³) - STP
Acetylene (ethyne)C2H2261.09211.17020.06820.0729
Air291.2051.2930.07520.0806
AmmoniaNH317.0310.7170.7690.04480.0480
ArgonAr39.9481.6611.78370.10370.1114
BenzeneC6H678.113.4860.2064
Blast furnace gas1.2500.0780
ButaneC4H1058.12.4892.520.15540.1562
Butylene (Butene)C4H856.112.5040.1482
Carbon dioxideCO244.011.8421.9770.11500.1234
Carbon monoxideCO28.011.1651.2500.07270.0780
Carbureted Water Gas0.048
ChlorineCl270.9062.9940.1869
Coal gas0.582
Coke Oven Gas0.0342
Combustion products1.1120.0692
Cyanogen (dicyan)2.332
Dichlorodifluoromethane (Freon F 12)CCl2F25.512
Digester Gas (Sewage or Biogas)0.062
EthaneC2H630.071.2640.0789
EthyleneC2H428.031.2600.0786
HeliumHe4.020.16640.17850.01040.0111
HydrogenH22.0160.08990.0056
Hydrochloric Acid36.471.632
Hydrogen ChlorideHCl36.51.5280.0954
Hydrogen SulfideH2S34.0761.4340.0895
Krypton3.742
MethaneCH416.0430.6680.7170.04170.0447
Natural gas19.50.7-0.920.044-0.056
NeonNe20.1790.89990.0562
Nitric oxideNO30.01.2490.0780
NitrogenN228.021.1651.25060.07270.0781
Nitrous OxideN2O44.0130.114
OxygenO2321.3311.42900.08310.0892
OzoneO348.02.1420.125
PropaneC3H844.091.8820.1175
Propene (propylene)C3H642.11.7480.1091
Sasol0.032
SulfurS32.060.135
Sulfur DioxideSO264.062.2792.9260.17030.1828
TolueneC7H892.1414.1110.2435
Water Vapor, steamH2O18.0160.8040.048
Water gas (bituminous)0.054
Xenon5.862
Calculator

Inputs

Results

Density-- lb/ft³