EK 1001 Chemistry 374 Heat of formation

[GRod18]

Another EK chem problem, thanks in advance!

The heat of formation of water vapor is.

Answer: Negative, but less negative than the heat of formation of liquid water.

What I don't understand is why is is less negative, since it is an exothermic reaction, wouldn't it release more heat when water is converted to vapor then when water is converted from ice? I don't really understand their explanation so any input would be appreciated

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[MediCynical]

Water molecules need more energy to be a vapor than to be a liquid, so some of the energy that would be released as heat must contribute to the increased energy necessary to be in the vaporous state vs a liquid state.