Chemistry · States of Matter - Gases, Liquids and Solids

When water freezes, the molecules form a crystalline structure maintained by hydrogen bonds, which causes them to be arranged further apart compared to when they are in liquid form. This expansion results in ice having a lower density than liquid water, allowing ice to float. The incorrect options do not accurately describe the behavior of water molecules during freezing: ionic bonds do not play a role, increased kinetic energy is associated with the liquid state, and the polarity of water molecules remains intact and is crucial for hydrogen bonding.

This option is incorrect because water molecules primarily form hydrogen bonds, not ionic bonds, which do not significantly affect the density of ice.

This is the correct answer. When water freezes, hydrogen bonds hold the molecules in a lattice structure that is less dense than liquid water, causing ice to expand.

This option is incorrect because increased kinetic energy typically leads to a state of matter that is less structured (liquid) rather than the orderly lattice structure found in ice.

This option is incorrect because water retains its polarity even in solid form. The polarity of water molecules is essential for the formation of hydrogen bonds.