Here is a picture of hot and cold air. Hot air rises while
cold air sinks. Cole air is denser than hot air. This is why gravity makes hot
air balloons rise. The denser cold air is pulled down and under the less dense
hot air. The molecules are packed closer together in cold air. Hot air moves
more than cold air. Technically, both are moving at the same “speed” since it
is simply the movement of energy by a process. Dry air is denser compared to
water vapor or humid air at the same temperature and pressure. The two
components in dry air are Oxygen and Nitrogen with a combined molar mass of
28.97. The components of water are Hydrogen and Oxygen with a molar mass of 16.
Hence, water vapor is lighter than dry air.
