Question

A 22.2-g piece of Al (which has a molar heat capacity of 24.03 J/mol°C) is heated to 84.6°C and dropped into a calorimeter containing water (the specific heat capacity of water is 4.18 J/g°C) initially at 23.5°C. The final temperature of the water is 27.8°C. Calculate the mass of water in the calorimeter.

Answer 1

heat lost by Al + heat gained by water = 0

[mass Al x specific heat Al x (Tfinal-Tinitial)] + [mass H2O x specific heat H2O x (Tfinal-Tinitial)] = 0
Substitute and solve for the only unknown in the problem (which is mass H2O)

Answer 2

12