When water (H₂O) freezes into ice, let's analyze what changes and what stays the same among the given properties:
1. Identity of the H₂O:
- When water freezes, it remains H₂O in its molecular form. The water molecules do not change chemically, so the identity of the H₂O molecules stays the same.
2. Energy of the H₂O:
- The process of freezing involves a loss of energy as water transitions from a liquid to a solid state. Thus, the energy of the H₂O changes during the freezing process.
3. Arrangement of the H₂O:
- In the liquid state, water molecules are randomly arranged and can move freely past one another. When it freezes, the molecules arrange themselves into a crystalline structure. Hence, the arrangement of the H₂O molecules changes.
4. Property of the H₂O:
- Properties such as density, volume, and the state of matter change when water freezes. Ice is less dense than liquid water, and it occupies more volume. Therefore, the properties of H₂O, including its physical state, change.
In summary, the identity of the H₂O (i.e., the chemical composition) remains the same, while the energy, arrangement, and various properties (like density and volume) change.
Therefore, what stays the same is the identity of the H₂O.
