The molar heats of combustion of three hydrocarbon gases are:
CH4 (methane)= - 890.0 kJ/mol
C2H6 (ethane)= - 1560.0 kJ/mol
C3H8 (propane)= - 2220.0 kJ/mol
Find the heat of combustion in kJ/g for each gas. These values are valid at 25°C, where the water produced by the reaction is in the liquid state.