Latent heat is the heat energy required to change the state of matter without a change in temperature.

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Multiple Choice

Latent heat is the heat energy required to change the state of matter without a change in temperature.

Latent heat is the energy involved in changing a substance’s phase without changing its temperature. When a solid melts or a liquid boils, energy goes into breaking intermolecular bonds rather than raising the temperature, so the temperature stays constant during the transition. This matches the statement as it describes heat energy required to change state without a temperature change. For example, ice must absorb latent heat of fusion to melt at 0°C, and liquid water must absorb latent heat of vaporization to become steam at 100°C; in both cases the temperature does not rise during the phase change. Heating a substance beyond its boiling point involves sensible heat, which increases temperature rather than causing a phase change at a constant temperature. The idea of heat removed during freezing refers to energy released during solidification, which is related to latent heat but describes the opposite direction; the general concept is about the energy needed (or released) to change state without a temperature change.

Latent heat is the energy involved in changing a substance’s phase without changing its temperature. When a solid melts or a liquid boils, energy goes into breaking intermolecular bonds rather than raising the temperature, so the temperature stays constant during the transition. This matches the statement as it describes heat energy required to change state without a temperature change. For example, ice must absorb latent heat of fusion to melt at 0°C, and liquid water must absorb latent heat of vaporization to become steam at 100°C; in both cases the temperature does not rise during the phase change. Heating a substance beyond its boiling point involves sensible heat, which increases temperature rather than causing a phase change at a constant temperature. The idea of heat removed during freezing refers to energy released during solidification, which is related to latent heat but describes the opposite direction; the general concept is about the energy needed (or released) to change state without a temperature change.

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