Heat is absorbed or released during a phase change as the latent heat of fusion or the latent heat of vaporization is absorbed or released. The temperature is constant during a phase change as all the energy goes into or comes our of potential energy. This is the definition of conduction. Relative humidity is a measure of how much water vapor is in the air compared to how much could be there at that temperature. Cool air will hold less water vapor than warm air, so cooling the air with no other changes will increase the relative humidity.
Temperature is a measure of the average kinetic energy of the molecules of a substance.
Thus cooler air has slower moving water vapor molecules and slower moving molecules spend more time close to each other than they do in warmer air. Thus in warmer air water vapor molecules are less likely to be attracted and pulled together than they would in cooler air, so warm air holds more water vapor. Click below to see one way to solve this problem. 80.6 o F. Click below to see one way to solve this problem. Click below to see one way to solve this problem.