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).

Given,

Mass of the copper block, m = 2.5 kg = 2500 g


Rise in the temperature of the copper block, ΔT = 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 that the copper block can lose, Q = mCΔT


Q = 2500 g × 0.39 J g–1 °C–1 × 500 °C


Q = 487500 J


Let m’ be the amount of ice that melts when the copper block is placed on the ice block.


So, the heat gained by the melted ice, Q = m’L


m’ = Q/L


m’ = 487500/335


m’ = 1455.22 g = 1.455 kg


Hence, the maximum amount of ice that can melt is 1.455 kg.


NOTE: The specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius.


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