Answer:
When water freezes, the molecules get themselves into the most stable  positions that have the minimum amount of energy in the resulting ice crystal. It so happens that the arrangement of water molecules that best satisfies this requirement is one that takes up even more space. And so ice expands when it freezes.
Explanation: Hope this could help! ^^
Explanation:
Water expands about 9% when it freezes. This happens because it's molecules decide to take a more solid like shape.
