Question

The heat of fusion for `Al` is `125` `Jg^-1`. How do you calculate the molar heat of fusion for `Al`?

Answer 1

The key thing needed is to know the molar mass of aluminium: `27` `gmol^−1`. If each gram of aluminium takes `125` `J` to vaporise it, and a mole is `27` `g`, then each mole takes `27×125=3,375` `Jmol^−1`.