A hot-water bottle contains 799 g of water at 53∘C. If the liquid water cools to body temperature (37 ∘C), how many kilojoules of heat could be transferred to sore muscles?

Answer 1

heat lost by water = heat gained by body

heat lost by water = q = mC∆T

m = mass = 799 g

C = specific heat of water = 4.184 J/g/deg

∆T = change in temperatuer = 53 - 37 deg = 16 degress

q = (799 g)(4.184 J/g/deg)(16 deg) = 53,488 J x 1kJ/1000 J = 53.488 kJ = 53.5 kJ (to 3 significant figures)