Question

The heat of fusion of water is 336 J/g. What is the molar heat of fusion (j/mol) of water?

Answer 1

`6050 J/(mol)`, or `6.05 (kJ)/(mol)`

Explanation:

Use the fact that one mole of water is equal to `18.02` grams of water:

`((336J)/(1cancel(gH_2O)))((18.02cancel(gH_2O))/(1molH_2O)) = 6050J/(mol)`

A more conventional unit for enthalpy of fusion, enthalpy of vaporization, etc. is kilojoules per mole, and is found by dividing the units in joules per mole by `10^3`:

`((6050cancelJ)/(1 molH_2O))((1kJ)/(10^3cancelJ)) = 6.05(kJ)/(mol)`