The cooling effect of sweating occurs because of the breaking of which chemical bonds?
The cooling effect of sweating occurs because of the breaking of NO chemical bonds.
Evaporation, the transition liquid to gas, is intrinsically an ENDOTHERMIC process, and certainly no chemical bonds have been broken in the given equation. However, a change of state has occurred. When the water evaporates its intrinsically high heat of vaporization must be supplied from somewhere, i.e. your body heat, and a cooling effect results.