SSC MTS 2024 PYQ — Question 49

The correct answer is  option 4  i.e. Both boiling and evaporation are bulk phenomena.

The incorrect statement is 'Both boiling and evaporation are bulk phenomena.'

Evaporation is a surface phenomenon where only molecules at the liquid’s surface escape into the air. It causes cooling because the higher-energy molecules leave, lowering the liquid’s temperature. Boiling, on the other hand, is a bulk phenomenon where vaporization occurs throughout the entire liquid once it reaches its boiling point. Thus, evaporation and boiling differ fundamentally in where they occur in the liquid. Saying both are bulk phenomena is wrong because evaporation happens only at the surface, not throughout the liquid.