CH4+O2⟶CO2+2H2O
Gram molecular mass of CO2 = 12 +2(16) = 44g/mol
From the reaction it is clear that 1 mole of methane on complete combustion produces 44g (1 mole) of carbon dioxide.
Therefore moles of CH4required to produce 22g of CO2 are:
=144×22=0.5 mol