Question

when is the process of sublimation useful​

Answer 1

The process of sublimation are useful for separating impurities like chlorine from water.

It can not be done through any other eay

Hope i helped☺

Answer 2

The process of sublimation is useful in the production of dry ice or solid carbon-dioxide. At -78.5 degree celsius under 1 atmospheric pressure carbon-dioxide is sublimed to produce dry ice which is used in the preservation of fish, vegetables etc.