A piece of copper at 90°C is added 2.200 KG of water at 15°C inside an aluminum calorimeter that has a mass of .100 KG the final temperature of the copper water and calorimeter is 25°C what is the mass of the copper piece

Answer 1

heat lost by Cu + heat gained by Al + heat gained by water = 0

[mass Cu x specific heat Cu x (Tfinal-Tinitial)] + [mass Al x specific heat Al x (Tfinal-Tinitial)] + [mass H2O x specific heat H2O x (Tfinal-Tinitial)] = 0

I would convert all to grams and use specific heat in J/g*C