Question

During which phase change does water release the most heat energy?

Answer 1

The phase change during which water releases the most heat energy is from liquid to gas, known as vaporization or boiling.

Step-by-step explanation:

The phase change during which water releases the most heat energy is from liquid to gas, known as vaporization or boiling.

When water reaches its boiling point at 100°C (at atmospheric pressure), it undergoes a phase change from liquid to gas. During this phase change, a significant amount of heat energy is absorbed by the water, which is known as the heat of vaporization. For water, the heat of vaporization is 2256 kJ/kg. This means that when 1 kg of liquid water is converted into steam, it absorbs 2256 kJ of heat energy. This is much higher than the heat energy absorbed during other phase changes, such as melting or freezing.

Answer 2

The phase change that releases the most energy is deposition, when gas turns into a solid. It takes the absorption of energy to melt a solid into a liquid, and even more energy to vaporize the liquid into a gas. Hence, the reverse process (from solid to gas) will result in the greatest release of energy.