Question

Water is unusual because it expands as it freezes. Very few substances have this property. The reason liquid water is more dense then ice can be best explained by?

Answer 1

It can be explained by its surface tension.

Answer 2

When the water freezes a reticulum is formed that occupies more space and is less dense than liquid water since the water on cooling decreases its volume. The reason why the water is denser in a liquid state is because, when it goes to a solid state, the water molecules are cold and still and the hydrogen bonds keep them constantly at the same fixed distance, while when they are in a liquid state, their hydrogen bonds are not at a fixed distance, but more separated.