The molar enthalpy of fusion for water is 6.008 kj/mol. what quantity of energy is released when 253g of liquid water freezes? (molar mass of water is 18.02 g/mol)

During freezing, energy is released by the mass of water without change in temperature. Such energy will also be required if the same mass of water has to be melted.

Then,

Number of moles = mass/molar mass = 253/18.02 =14.04 moles

Energy released = moles*molar enthalpy of fusion = 14.04*6.008 = 84.35 kJ