Latent heat of vaporization refers to the heat exchanged during which phase change?

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Multiple Choice

Latent heat of vaporization refers to the heat exchanged during which phase change?

Latent heat of vaporization is the energy required to change a liquid into a gas at its boiling point, with no change in temperature. When a liquid boils, heat goes into breaking the intermolecular forces that hold the liquid together, allowing molecules to escape as a gas. This is why the temperature stays the same during the phase change—the heat is used for the phase change itself, not for warming the substance. This is different from melting, which is latent heat of fusion (solid to liquid), and from heating without a phase change, which raises temperature (sensibly heating the substance). Gas to solid (deposition) or solid to gas (sublimation) are other phase changes with their own latent heats. So the vaporization process is the liquid-to-gas transition.

Latent heat of vaporization is the energy required to change a liquid into a gas at its boiling point, with no change in temperature. When a liquid boils, heat goes into breaking the intermolecular forces that hold the liquid together, allowing molecules to escape as a gas. This is why the temperature stays the same during the phase change—the heat is used for the phase change itself, not for warming the substance.

This is different from melting, which is latent heat of fusion (solid to liquid), and from heating without a phase change, which raises temperature (sensibly heating the substance). Gas to solid (deposition) or solid to gas (sublimation) are other phase changes with their own latent heats. So the vaporization process is the liquid-to-gas transition.

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