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How does heat of fusion differ from heat of vaporization?

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heating In a thermoelectric generating system a heat source—usually fueled by coal, oil, or gas—is used within a boiler to convert water to high-pressure steam. The steam expands and turns the blades of a turbine, which turns the armature of a generator, producing electric power. A condenser converts any remaining steam to water, and a pump returns the water to the boiler.

Latent heat refers to the energy absorbed or released by a substance during a phase change without a change in temperature. The primary difference between the heat of fusion and the heat of vaporization lies in the specific phase transitions they facilitate:

Heat of fusion: This is the energy required to transition a substance from a solid to a liquid at its melting point. It provides the necessary energy to overcome the attractive forces holding atoms or molecules in a rigid crystalline solid lattice, allowing them to move freely as a liquid.12
Heat of vaporization: This is the energy required to convert a liquid into a gas or vapour at its boiling point. It is used to break the remaining long-range order and cohesive forces of the liquid, enabling particles to move independently in the much larger volume of a gaseous state.13

Generally, the heat of vaporization is significantly larger than the heat of fusion because transitioning to a gaseous state requires overcoming more substantial intermolecular forces to achieve complete particle independence.1