Question

An unknown material has a normal melting/freezing point of -20.4 °C, and the liquid phase has a specific heat capacity of 179 J/(kg C°). One-tenth of a kilogram of the solid at -20.4 °C is put into a 0.130-kg aluminum calorimeter cup that contains 0.198 kg of glycerin. The temperature of the cup and the glycerin is initially 26.4 °C. All the unknown material melts, and the final temperature at equilibrium is 19.1 °C. The calorimeter neither loses energy to nor gains energy from the external environment. What is the latent heat of fusion of the unknown material?

Answer 1

19.4

Answer 2

19.4