What is the percent by mass of zinc and ZnCO3

This energy required is the latent heat, which is required for physical transformations. Specifically, when it involves changing liquid to gas, this latent heat is called the heat of vaporization. The formula is:

Q = mΔHvap
The molar mass of the compound is 
Q = (48.7 g)(31.6 kJ/mol)(1 mol/84.93 g)
Q = 18.12 kJ