Calorimetry — Question 4

Given,

m = 150 g = 0.15 kg

P = 100 W

t = 4 min = 240 s

specific latent heat of fusion of the metal = ?

Heat supplied = P x t

Substituting the values we get,

$\text{Heat supplied} = 100 \times 240 \\[0.5em] \text{Heat supplied} = 24000 J$

We know,

Q = m x L

Substituting the values we get,

$24000 = 0.15 \times \text{L} \\[0.5em] \Rightarrow \text{L} = \dfrac{24000}{0.15} \\[0.5em] \Rightarrow \text{L} = 160,000 \\[0.5em] \Rightarrow \text{L} = 1.6 \times 10^{5} \text{ J kg}^{-1}$

Hence, specific latent heat of fusion of the metal = 1.6 x 10⁵ J kg^-1