When water [tex]\(\left( \text{H}_2 \text{O} \right)\)[/tex] freezes into ice, several properties of the water change, but some remain the same. Let's analyze each given option:
1. Identity of the [tex]\(\text{H}_2 \text{O}\)[/tex]:
- The chemical identity of the water molecules remains the same when water freezes into ice. Each molecule of water still consists of two hydrogen atoms and one oxygen atom ([tex]\(\text{H}_2 \text{O}\)[/tex]), regardless of whether it is in liquid or solid state.
2. Energy of the [tex]\(\text{H}_2 \text{O}\)[/tex]:
- When water freezes, its temperature decreases, and the system loses energy. The molecules have less kinetic energy in the solid state compared to the liquid state.
3. Arrangement of the [tex]\(\text{H}_2 \text{O}\)[/tex]:
- The arrangement of water molecules changes significantly when it transitions from liquid to solid. In the liquid state, molecules are constantly moving and have a more disordered structure. In contrast, in the solid state (ice), molecules form a crystalline structure that is highly ordered.
4. Property of the [tex]\(\text{H}_2 \text{O}\)[/tex]:
- Some properties change, such as density (ice is less dense than liquid water) and volume (water expands when it freezes). However, the chemical properties remain the same.
Considering these points, what stays the same when water freezes into ice is the identity of the [tex]\(\text{H}_2 \text{O}\)[/tex] molecules. The molecular composition does not change, and water remains [tex]\(\text{H}_2 \text{O}\)[/tex] in both liquid and solid states. Therefore, the answer is:
Identity of the [tex]\(\text{H}_2 \text{O}\)[/tex].
