Question

Why is ice less dense than water?

Answer 1

1. In water, each bond between Hydrogen and Oxygen is polar due to the high electronegativity of Oxygen.
2. Due to the polar nature of water molecules, the water molecules are attached by intermolecular Hydrogen bonding.
3. Ice has an organized three-dimensional structure containing Hydrogen bonds.
4. It has an open structure and several wide gaps due to Hydrogen bonding. So, there is a lowering in the volume of ice.
5. Hence, the density of ice is low.
6. When the ice melts, some of the hydrogen bonds are broken and the water molecules enter the gaps present in the ice.
7. So, the structure of liquid water is less open than the structure of ice.
8. Hence, ice is less dense than water.