Question

Heat energy required to melt $10kg$ ice at its melting point will be _____. (The latent heat of fusion of water = $333.55kJk{g}^{-1}$).

• A. $2.33\times {10}^{6}J$
• B. $3.33\times {10}^{6}J$
• C. $4.33\times {10}^{5}J$
• D. $4.33\times {10}^{4}J$

Answer 1

The correct option is B

$3.33\times {10}^{6}J$

Given:
Mass of ice, $m=10kg$
Latent heat, $L=333.55kJ/kg$
Heat needed to melt $1kg$ of ice is equal to its latent heat of fusion. (Since, there is a phase change)
Heat required = $m\times L$
$\Rightarrow 10\times 333.55=3.33\times {10}^{3}kJ$
$1000J=1kJ$
$\therefore 3.33\times {10}^{3}kJ=3.33\times {10}^{6}J$.