1. The problem statement, all variables and given/known data When a liquid freezes, it gives out heat. Where does this heat come from? 2. Relevant equations none 3. The attempt at a solution Does this only apply to water or other chemical substances as well. The heat comes from the strong bonding when as a liquid. But now this kind of potential energy stored in the bonds is released into kinetic energy hence heat outflow. This explanation is only for water as the liquid state has stronger bonding hence higher potential energy in the liquid bonds. But what about other chemical substances?