Question

Usually liquids have lower density than solids, yet ice floats in water. Can you say why?
Ice is lighter than water since a particular mass of ice occupies more space than the same mass of water. In ice, water molecules are closely packed because of the tight bonding between them. This makes ice lighter than water.
Now my Question is:
If the molecules of water are closely packed in ice then why the density of water is higher than ice and how it makes ice lighter than water?

Answer 1

Dear student,
When water freezes into ice it expands this is known as anamolous expansion of water hence the density deceases as a result it floats in water. But the formation of ice takes place due to the hydrogen bonds which exist and not because the molecules are tightly packed. These hydrogen bonds are comparatively large which results in increase in volume.
Regards