Question

How much energy is required to melt 450 g of ice at 0 degree Celsius.
a) 1500kJ b) 1600kJ c) 150kJ d) none of these

Answer 1

None of these.

Heating a substance has sensible effects and latent effects. Sensible effects are when a substance absorbs or releases energy and changes temperature within the same phase. Latent effects are when a substance absorbs or releases energy, remains at the same temperature, but changes phase.

Here, assuming we are at 1 atmosphere of pressure, we have a solid substance already at its melting point. This means the energy will go solely into latent effects and we will experience no sensible effects until all of the substance has melted.

The latent heat of fusion for water is 334 joules per gram. (45.0 g)(334 J/g)=15000 J=15 kJ

Answer 2

(d) none of these.......