What is moist air? Air can be considered a mixture of dry air and water vapor. If it contains water vapor it's called moist air, but the air's humidity can vary within broad limits. Extremes are completely dry air and air saturated with moisture.

Why is moist air?

It does not matter what the gas is — the same number of molecules will exist in that volume. To make a given volume of air moister, we need to add water vapor molecules to the volume. ... Therefore, moist air is lighter than dry air if both are at the same temperature and pressure.

What is moist air in chemistry?

Moist air like dry air is a mixture. It has no chemical formula apart from the chemical formulae of its component parts. So H20 is the chemical formulae of the water component of moist air. O2 is the chemical formula of the oxygen component comprising moist air.