2.0kg of water at 0 degree celsius is to be changed into ice at this temperature. The same mass of water now at 100 degree celsius is to be changed into steam at this temperature.

Question

specific latent heat of fusion of water= 3.34 x10^5 J kg^-1.
specific latent heat of vaporization of water=2.26x10^6 J kg^-1
a)calculate the amount of energy needed to be removed from the water to freeze it.
b)calculate the amount of energy required by the water to vaporize it.
c)explain the difference between the values calculated in a) and b).
help

Answer 1

a and b are strightforward calculations.
c. The difference is due to the energy needed to remove water molecules from their common attraction when liquid: In vaporizaiton, they are removed completely. In freezing, they are not removed at all. And, in freezing, you remove energy from them, in vaporization, you add energy to them.

Answer 2

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