Why Heat Of Vaporization Is Larger Than Heat Of Fusion
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Why Heat Of Vaporization Is Larger Than Heat Of Fusion

Why is heat of vaporization larger than heat of fusion?

The strings:

S7P3A32 (Force - Push)

The math:
Pj Problem of Interest is of type force. Energy is the capacity for work. It is force that is the doer of the work. So energy and work problems are of type force. In this instance, the energy is heat energy which is a consequence of kinetic energy. The kinetic energy is due to atom collisions (force-push). It is in this sense that the Pj Problem of interest is of type force.

Heat Of Vaporization: the quantity of heat required to vaporize 1 gram of a liquid substance at its boiling point at constant temperature. In other words, amount of heat needed to change a substance from the liquid phase to a gas phase.
Heat Of Fusion: the quantity of heat required to liquefy 1 gram of a solid substance at its melting point at constant temperature. in other words, amount of heat needed to change a substance from the solid phase to the liquid phase.

Vaporization and fusion are phase changes. The volume-increase in a liquid to gas phase change is larger than the volume-increase in a solid to liquid phase change. Since work is the product of pressure and change in volume, more work is required (at constant pressure) for vaporization than for fusion. Hence more energy (heat energy) is required for vaporization than for fusion.

Implicit in the volume increase as a result of the phase changes are the relative molecular distances. The molecules of a substance are so much further apart when the substance is in a gaseous state than when it is in a liquid state. The separation of the molecules of a substance requires energy. This energy is directly proportional to the intermolecular distance realized. In other words, a lager energy is required to keep the molecules of a substance further apart. Consequently, the heat of vaporization is larger than the heat of fusion.

Blessed are they that have not seen, and yet have believed. John 20:29