Question

Ice has lower density than water because :

• A. hydrogen bonding
• B. hydrogen bonding and cage like structure of ice
• C. bent structure of water
• D. diamond structure of water

Answer 1

Answer: (B)

hydrogen bonding and cage like structure of ice

Ice has a lower density than water because of hydrogen bonding and cage-like structure of ice.
Ice has hexagonal three-dimensional crystal structure (as per X-ray crystallographic data). This hexagonal crystal structure is formed due to intermolecular hydrogen bonding.
When ice melts, some of hydrogen bonds break and some empty spaces are occupied by water molecules. Liquid water molecules are more closely packed than molecules in ice. Hence, ice has lower density than water.