We’re being asked to determine the heat (q) of the evaporation of 451 g of water at 373 K.

Recall that heat will be absorbed when water is being evaporated (**phase change**). *Calculate heat (q) using the equation:*

$\overline{){\mathbf{q}}{\mathbf{=}}{\mathbf{n}}{\mathbf{\xb7}}{\mathbf{\u2206}}{{\mathbf{H}}}_{{\mathbf{vap}}}}$

q = heat, J

n = number of moles (mol)

ΔH_{vap} = heat of vaporization, kJ/mol

The heat of vaporization of water at 373 K is 40.7 kJ/mol.

Find q for the evaporation of 451 g of water at this temperature.