Freezing involves a chemical reaction

The two main chemical reactions that are involved in the change of state are exothermic reaction and endothermic.
Just as their name suggests, endothermic is when heat is ‘taken in’ and exothermic when heat is ‘given out’.
Freezing is not a CHEMICAL CHANGE, but indeed a physical one because it goes through change of state.
So in freezing a liquid converts to a solid.
For this change to happen, temperatures need to be lower and molecules in the liquid require less energy to join together, so it releases energy in the form of heat.
This reaction will be known as EXOTHERMIC REACTION.

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