Question

A 3.40 kg block of copper at a temperature of 74 °C is dropped into a bucket containing a mixture of ice and water whose total mass is 1.20 kg. When thermal equilibrium is reached the temperature of the water is 14 °C. How much ice was in the bucket before the copper block was placed in it?(ci = 2000 J/(kg.°C), cw = 4186 J/(kg.°C), Lf=3.35 × 105 J/kg, Lv=2.26 × 106 J/kg, ccopper = 387 J/(kg.°C). Neglect the heat capacity of the bucket.)