Question

freezing liquid
you may have noticed that ice floats in water, while most other solids sink in water. for most substances, the solid state is denser than the liquid state because the particles in the solid are packed more closely together. however, ice is less dense than liquid water.

1. for solid water (ice) to be less dense than liquid water, what must be true of the arrangement of the water molecules in ice?

Explanation:

Water molecules in ice form a hexagonal - lattice structure with open spaces between them. In liquid water, the molecules are more closely packed due to hydrogen - bonding and random motion. This open structure in ice makes it less dense than liquid water.

Answer:

The water molecules in ice are arranged in a more open, less - closely - packed structure compared to liquid water.