Question

A copper block of mass $5.0 kg$ 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: $0.39\, Jg ^{-1 \circ} C ^{-1}$ and latent heat of fusion of water : $335\, J g ^{-1}$ ]

• 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}=2.910\, kg$