Is methane lighter than air?

Is methane lighter than air?

• A. Yes
• B. No
• C. It depends on temperature
• D. It is heavier than air

Answer: (A)

Methane is lighter than air because it has a much lower molar mass than air. Methane’s molar mass is about 16 g/mol, while air is about 29 g/mol, so methane is roughly half as dense as air at typical temperatures and pressures. This means when methane is released, it tends to rise and accumulate near the ceiling in enclosed spaces, which is a key safety consideration in mines and other settings. While changes in temperature and pressure affect gas densities, methane remains lighter than air across common environmental ranges, so the general statement holds in practical situations. The other options would imply a different relationship that doesn’t apply under ordinary conditions.

Methane is lighter than air because it has a much lower molar mass than air. Methane’s molar mass is about 16 g/mol, while air is about 29 g/mol, so methane is roughly half as dense as air at typical temperatures and pressures. This means when methane is released, it tends to rise and accumulate near the ceiling in enclosed spaces, which is a key safety consideration in mines and other settings.

While changes in temperature and pressure affect gas densities, methane remains lighter than air across common environmental ranges, so the general statement holds in practical situations. The other options would imply a different relationship that doesn’t apply under ordinary conditions.