Chapter 9, Problem 99E

Evaporating sweat cools the body because evaporation is an endothermic process:
${\text{H}}_{\text{2}}\text{O}\left(l\right)\to {\text{H}}_{\text{2}}\text{O}\left(g\right)\Delta {\text{H}}_{\text{rxn}}^{\text{o}}\text{= +44}\text{.01 kJ}$
Estimate the mass of water that must evaporate from the skin to cool the body by 0.50 °C. Assume a body mass of 95 kg and assume that the specific heat capacity of the body is 4.0 J/g • °C.