A furnace that provides heat by burning methane gas (CH4) must have the correct mixture of air and fuel to operate efficiently. What is the mole ratio of air to methane gas in the combustion of methane? Air is 20% oxygen.

Question

callisto · Answer

$$2O _{2}+CH _{4} -> CO _{2}+2H _{2}O$$
For complete combustion of 1mole CH4
we need 2 moles of oxygen
Hence no. of mole of air required = 2/20% = 10 moles
therefore, mole ratio required is 10:1