What is the ratio of parts of methane combined with parts of oxygen for complete combustion?

The correct answer is based on the stoichiometric equation for the complete combustion of methane (CH₄). In this reaction, methane reacts with oxygen to produce carbon dioxide and water. The balanced chemical equation for this reaction is:

[ CH₄ + 2O₂ \rightarrow CO₂ + 2H₂O ]

From this equation, we see that one molecule (or part) of methane requires two molecules (or parts) of oxygen for complete combustion. This establishes the stoichiometric ratio of methane to oxygen as 1:2.

Understanding this ratio is crucial in applications such as combustion engines, gas appliances, and environmental science, where optimal fuel-to-oxygen ratios are needed for efficient combustion and to minimize the production of harmful emissions.