Question

In an experiment, 17 g of ice is used to bring down the temperature of 40 g of water at ${34}^{\circ }C$ to its freezing temperature. The specific heat capacity of water is 4.2 J $g^{-1}{K}^{-1}$. Calculate the specific latent heat of ice. State one important assumption made in the above calculation.

Answer 1

Heat lost by water at ${34}^{o}C$ to convert to water at $0^{o}C$ = $40\times 4.2\times 34=5712J$

Heat required to melt 17 g of ice = $17\times L$

Now, $17\times L=5712$

$\therefore L=336J/g$

Here, we have assumed that there is no loss of energy.