To calculate the number of moles of methane required to produce 22 g of CO2, we need to use the stoichiometry of the combustion reaction of methane:

CH4 + 2O2 -> CO2 + 2H2O

From this equation, we can see that 1 mole of methane (CH4) reacts with 1 mole of CO2. Therefore, the number of moles of methane required to produce 22 g of CO2 can be calculated as follows:

Moles of CO2 = mass of CO2 / molar mass of CO2

Moles of CO2 = 22 g / 44 g/mol

Moles of CO2 = 0.5 mol

Since 1 mole of methane produces 1 mole of CO2, the number of moles of methane required to produce 0.5 mol of CO2 is also 0.5 mol.

Therefore, 0.5 moles of methane are required to produce 22 g of CO2.