Table A: Enthalpy of Formation Values for Various Substances
Student Guide (continued)

Substance
Hf (kJ/mol)
NH3(g)
–46.11
NO2(g)
+33.18
CH4(g)
–74.81
C2H4(g)
+52.26
C2H6(g)
–84.68
C3H8(g)
–103.85
C3H6(g)
+20.42
CO2(g)
–393.51
H2O(g)
–241.82
CH3OH(l)
–238.86
Table B: Enthalpy of Formation of Reactants and Products
Substance
Hf (kJ/mol)