Question

on heating a sublimable solid the molecules break free and escape from surface of the solid directly into vapour

Answer 1

Answer:

The kinetic energy of the particles at the surface of a sublimable substance is high due to which on heating, these particles acquire energy  and overcome the inter particle forces of attraction. Such solids directly change into gases.

Explanation:

Answer 2

Answer:

On heating a sublimable solid the inter-particle attraction is overcome and the molecules break-free and escapes from the surface of the solid directly into the vapour.