If you camp outside, you often find that in the morning, it’s wet on the outside. Other solids also seem wet. Why? FIrst of all, is water vapour always around us at night and day? At around midnight, the air and tent is at their coldest. When the sun slowly rises, it heats up the tent and air but the tent raises its temperature more slowly than air hence there is disequilibrium. Solids generally heat more slowly due to the fact that air can receive a smaller amount of energy per degree rise in temperature than solid because the intermolecular forces between water is much lower than that between solids. At the higher temperature, it’s now more thermodynamically favourable for the water vapour to condense into liquid and give off heat to the tent, which is at a lower temperature. So the main reason is that water vapour can raise its temperture more easily than solids.