Specific Heat Capacities of Gases

**Specific Heat Capacities of Gases**
Gas	Formula	Specific heat capacity (Btu/lb·°F)		Specific heat capacity (kJ/kg·K)		Gas constant (=Cₚ-Cᵥ) (ft lb/lb·°F)	Gas constant (=Cₚ-Cᵥ) (kJ/kg·K)
Gas	Formula	Cₚ	Cᵥ	Cₚ	Cᵥ	Gas constant (=Cₚ-Cᵥ) (ft lb/lb·°F)	Gas constant (=Cₚ-Cᵥ) (kJ/kg·K)
Acetylene	C₂H₂	0.380	0.270	1.47	1.13	59.34	0.34
Air	—	0.251	0.171	1.01	0.716	53.34	0.29
Ammonia	NH₃	0.523	0.399	2.19	1.67	96.50	0.52
Blast furnace gas	—	0.245	0.174	1.03	0.729	55.05	0.297
Carbon dioxide	CO₂	0.210	0.160	0.827	0.632	38.86	0.189
Carbon monoxide	CO	0.243	0.172	1.02	0.720	55.14	0.297
Combustion products	—	0.24	—	1.01	—	—	—
Ethylene	C₂H₄	0.400	0.330	1.67	1.38	55.08	0.29
Hydrogen	H₂	3.42	2.44	14.24	10.08	765.90	4.16
Methane	CH₄	0.593	0.450	2.23	1.71	111.31	0.60
Nitrogen	N₂	0.247	0.176	1.034	0.737	54.99	0.297
Oxygen	O₂	0.219	0.157	0.910	0.656	48.24	0.260
Sulphur dioxide	SO₂	0.154	0.123	0.645	0.515	24.10	0.130

SOURCE: Data adapted from standard engineering references for specific heat capacities of gases.