What happens to the energy of water when it freezes?

When water freezes, the molecules transition from a liquid state to a solid state. During this process, the energy of water is released into the surrounding environment. This is because the formation of solid ice involves the creation of hydrogen bonds between water molecules, which occurs as the molecules slow down and get closer together. As these bonds form, energy is released.

This energy release is often experienced as a decrease in temperature in the surrounding area, which is why freezing can feel cold and is also a process often associated with the term "exothermic." In contrast, if energy were added, the water would remain a liquid or turn into vapor, and if energy remained constant, there would be no change in the state of the water. Thus, the correct understanding is that during the freezing process, energy is indeed released.