CBSE Class 9 Answered

The enthalpy of fusion or heat of fusion is the change in enthalpy resulting from heating a given quantity of a substance to change its state from a solid to a liquid. The temperature at which this occurs is the melting point.

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Latent heat of fusion is the heat required to change 1 kg of a solid substance into liquid state at the melting point of the substance. Example, amount of heat required to melt ice at 0° C into water at 0° C, will be known as the Latent Heat of Fusion of ice.