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Gas Density

Reference data and engineering information about gas density for gases and compressed air applications.

gasdensityData Table

Overview

Engineering reference data for Gas Density in gases and compressed air.

Key Formulas

Ideal Gas Law

PV=nRTPV = nRT

Pressure × Volume = moles × gas constant × temperature.

Boyle's Law

P1V1=P2V2P_1 V_1 = P_2 V_2

At constant temperature.

Charles's Law

V1T1=V2T2\frac{V_1}{T_1} = \frac{V_2}{T_2}

At constant pressure.

Variables

SymbolDescriptionUnit
PPPressurePa
VVVolume
TTTemperatureK
RRGas constant8.314 J/(mol·K)

Gas Density Data Table

17 rows
Densities of common gases at NTP (20°C, 1 atm) and STP (0°C, 1 atm). Note: Molecular weight values are in g/mol.
Gas
Formula
Molecular Weight(g/mol)
Density (NTP)(kg/m³)
Density (STP)(kg/m³)
Density (NTP)(lb/ft³)
Density (STP)(lb/ft³)
Acetylene (ethyne)C₂H₂261.0921.170.06820.0729
Air291.2051.2930.07520.0806
AmmoniaNH₃17.0310.7170.7690.04480.048
ArgonAr39.9481.6611.7840.10370.1114
BenzeneC₆H₆78.113.4860.2064
ButaneC₄H₁₀58.12.4892.520.15540.156
Carbon dioxideCO₂44.011.8421.9770.1150.1234
Carbon monoxideCO28.011.1651.250.07270.078
EthaneC₂H₆30.071.2640.0789
EthyleneC₂H₄28.031.260.0786
HeliumHe4.020.16640.17850.010390.01114
HydrogenH₂2.0160.08990.0056
MethaneCH₄16.0430.6680.7170.04170.0447
NitrogenN₂28.021.1651.2510.07270.0781
OxygenO₂321.3311.4290.08310.0892
PropaneC₃H₈44.091.8820.1175
Sulfur dioxideSO₂64.062.2792.9260.17030.1828

Source: engineeringtoolbox.com

Note on Conditions:

  • NTP (Normal Temperature and Pressure): 20°C (68°F), 1 atm.
  • STP (Standard Temperature and Pressure): 0°C (32°F), 1 atm.

Interactive Charts

Air - Molecular Weight and Composition

References