Question

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

Answer 1

Mass of the copper block, $m=2.5kg=2500g$
Rise in the temperature of the copper block, $={500}^{o}C$
Specific heat of copper, $C=0.39J/g^{o}C$
Heat of fusion of water, $L=335J/g$
The maximum heat the copper block can lose,

$Q=mC$
$=2500\times 0.39\times 500$

$=487500J$

Let $m_1$ 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,$Q=m_{1}L$

$m_1=Q/L=487500/335=1455.22g$

Hence, the maximum amount of ice that can melt is 1.45 kg.