Which formula represents the latent heat for a substance changing state?

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Multiple Choice

Which formula represents the latent heat for a substance changing state?

Latent heat is the energy needed for a substance to change its state without changing its temperature. During a phase change, temperature stays constant, and the energy goes into breaking or forming bonds between particles. The amount of energy involved is proportional to how much substance is changing state, with the proportionality constant L being the latent heat per unit mass. That gives the relation Q = mL, where Q is the heat absorbed or released and m is the mass. If you rearrange it, you can also write L = Q/m, but the core idea is that the heat associated with a state change equals mass times the latent heat per mass. The other common formula, Q = mcΔT, applies to heating or cooling where temperature changes without a phase change, so it’s not used to describe latent heat.

Latent heat is the energy needed for a substance to change its state without changing its temperature. During a phase change, temperature stays constant, and the energy goes into breaking or forming bonds between particles. The amount of energy involved is proportional to how much substance is changing state, with the proportionality constant L being the latent heat per unit mass. That gives the relation Q = mL, where Q is the heat absorbed or released and m is the mass. If you rearrange it, you can also write L = Q/m, but the core idea is that the heat associated with a state change equals mass times the latent heat per mass. The other common formula, Q = mcΔT, applies to heating or cooling where temperature changes without a phase change, so it’s not used to describe latent heat.

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