Question

A copper block of mass $5.0kg$ is heated to a temperature of $500^{\circ }C$ and is placed on a large ice block. What is the maximum amount of ice that can melt? [Specific heat of copper: $0.39J{g}^{-1\circ }{C}^{-1}$ and latent heat of fusion of water : $335J{g}^{-1}$ ]

• A. 1.5 kg
• B. 5.8 kg
• C. 2.9 kg
• D. 3.8 kg

Answer 1

Answer: (C)

Heat given by block to get $0^{\circ }C$ temperature
$\Delta Q_1=5\times \left(0.39\times 10^3\right)\times (500-0)$
$=975\times 10^{3}J$
Heat absorbed by ice to melt mass
$\Delta Q_2=m\times \left(335\times 10^3\right)J$
$\Delta Q_1=\Delta Q_2$
$m\times \left(335\times 10^3\right)=975\times 10^3$
$m=\frac{975}{335}=2.910kg$