The balanced chemical equation for the combustion of methane CH4 in the presence of oxygen O2 is:CH4 + 2O2 CO2 + 2H2OIf 10 moles of methane are combusted completely, the theoretical yield of carbon dioxide CO2 can be calculated using the stoichiometry of the balanced equation. Since there is a 1:1 ratio between methane and carbon dioxide, the theoretical yield of CO2 will be the same as the moles of methane.Therefore, the theoretical yield of CO2 is 10 moles.