Air with water vapor is lighter than dry air without water vapor. This is because water vapor (H₂O) has a lower molecular weight (approximately 18 g/mol) compared to the average molecular weight of the other components of dry air, which is about 29 g/mol (largely composed of nitrogen and oxygen). When water vapor replaces some of the nitrogen and oxygen in the air, the overall density of the air decreases, making it lighter.
Would air with water vapor be heavier or lighter than normal air without water vapor?
lighter
heavier
1 answer