Question

A copper block of mass 2.5 kg is heated in a furnace to a temperature of 500 °C and then placed on a large ice block. What is the maximum amount of ice that can melt? (Specific heat of copper = 0.39 J g^–1 K^–1; heat of fusion of water = 335 J g^–1).

Answer 1

Mass of the copper block, m = 2.5 kg = 2500 g
Rise in the temperature of the copper block, Δθ = 500°C
Specific heat of copper, C = 0.39 J g^–1 °C^–1
Heat of fusion of water, L = 335 J g^–1
The maximum heat the copper block can lose, Q = mCΔθ 
= 2500 × 0.39 × 500
= 487500 J 
Let m1 g be the amount of ice that melts when the copper block is placed on the ice block.
The heat gained by the melted ice, Q = m1L 
∴ m₁ = \(\frac{Q}{L}\) = \(\frac{487500}{335}\) = 1455.22 g
Hence, the maximum amount of ice that can melt is 1.45 kg.