A town gas has the following composition (by volume) CH4-40% H2-55% CO-5% the heats of the?

... components of the gas are;
CH4= -890kJ
H2= -286kJ
CO= -283kJ

a) write an equation for each of the reactions which occureswhen the town gas undergoes complete combustion. relate the equations to the enthalpy data.
b) calculate the volume of air (assuming it contains 21% oxygen) require to fully combust 5 liters of the town gas