How is the Hfusion used to calculate the energy required to vaporize a volume of liquid

Here's what I find

Explanation:

You don't use ΔHfus. You use ΔHvap

There are some preliminary calculations:

Use the density of the liquid to calculate its mass. Use the molar mass to calculate the moles (n)

The formula for the heat (q) absorbed during vaporization is

q = nΔHvap

Insert your numbers into the formula, do the calculation, and you have the answer.