Why is the time needed to vaporize the sample of water significantly greater than the time needed to melt the sample? A) Significantly more energy is needed to lower the kinetic energy of the molecules. B) Significantly more energy is needed because ice has a lower kinetic energy than liquid water. C) Significantly more energy is required since water vapor (steam) is so much hotter than liquid water. D) Significantly more energy is required to vaporize water because the intermolecular forces between molecules are being completely broken.

D) Significantly more energy is required to vaporize water because the intermolecular forces between molecules are being completely broken.

Explanation:

Different states of matter differ because of intermolecular distance between them. Molecules are closest in solid state and farthest in gaseous state. To separate them energy is needed. When matter changes state from liquid to gas, the distance between the molecule increases enormously. Hence energy requirement too is large. When matter changes state from solid to liquid, their mutual separation does not increase much so energy requirement too is lesser. Moreover there is tremendous increase in their volume in gaseous state due to which gas has to do work against external pressure which requires much energy.