Question

If 5g of a solid requires 30cal of heat to change into liquid at the same temperature, calculate the latent heat of fusion in cal/g.

(a) 150

(b) 0.167

(c) 6

(d) 3

I had been asked this question at a job interview.

I'm obligated to ask this question of Thermal Properties of Matter topic in division Thermal Properties of Matter of Physics – Class 11

Answer 1

The correct choice is (c) 6

Easiest explanation: For changing a solid into liquid, heat has to be supplied and this change occurs at constant temperature.                                                                                                                                                                             Q = mL

⇒ 30 = 5L

⇒ L = 6 cal/g,