Question

Why is the heat of vaporization of a molecule with a molecular mass of 346.2 g/mol higher than the heat of vaporization of a molecule with a molar mass of 157.4 g/mol?

Answer 1

the amount of heat necessary to boil (or condense) 1.00 mole of a substance at its boiling point

so if mass is more obviously it require more heat to boil it or

you can see mathamitically

q = ΔH_vap (mass/molar mass)

q is the total amount of heat involved

ΔH_vap is the symbol for the molar heat of vaporization. This value is a constant for a given substance

(mass/molar mass) is the division to get the number of moles of substance

from this equaation q is directly propotional to mass

if mass is more Q is also more