Problem 1: How much heat does your body lose when 2.3 g of sweat evaporates from your skin at 25 ∘C? (Assume that the sweat is only water.) The heat of vaporization of water at 25 ∘C is 44.0 kJ/mol. Problem 2: How much heat does your body lose when 4.15 g of sweat evaporates from your skin at 25 ∘C? (Assume that the sweat is only water.) The heat of vaporization of water at 25 ∘C is 44.0 kJ/mol.