Question

How much energy is required to melt 10.0 g of water at 0°C? (ΔH°fus = 6.01 kJ/mol; ΔH°vap = 40.76 kJ/mol; c = 75.3 J/mol • °C)

Answer 1

Energy is required to melt 10.0 g of water at 0°C

Given- ΔH°fus = 6.01 kJ/mol

Heat of fusion is the measure of the intramolecular energy which holds the molecules together and prevents them from a phase change without adding energy. In other word it's the amount of energy needed to change water from a solid to a liquid state.

In this case ΔH°fus = 6.01 kJ/mol, so convert 10g water into mol of water

Since a mole of water weighs 18 grams

10 grams of water = 10/18ths mol

q = (10.0 g / 18.0 g /mol) (6.01 kJ/mol) =3.34KJ

3.34KJ energy is required to melt 10.0 g of water at 0°C.