Final answer:
The mole ratio of methane to carbon dioxide in the reaction CH4 + 2O2 → CO2 + 2H2O is 1:1, meaning one mole of methane reacts to produce one mole of carbon dioxide.
Step-by-step explanation:
The mole ratio of methane (CH4) to carbon dioxide (CO2) in the balanced chemical equation CH4 + 2O2 → CO2 + 2H2O is 1:1. This means for every one mole of methane that reacts, one mole of carbon dioxide is produced. This ratio is derived from the coefficients of the respective substances in the balanced equation, which indicate the relative numbers of moles of each compound that are involved in the reaction.