Andre heated several solid crystals of a substance called iodine, and the iodine changed directly to a gas. The iodine gas then cooled and changed into droplets.

Which two processes did the iodine undergo?

A. condensation, then vaporization

B. sublimation, then condensation

C. deposition, then sublimation

D. vaporization, then deposition

The correct choice is

B. sublimation, then condensation

Sublimation is the name of the process where a solid directly converts into gas on heating. on heating solid crystals of iodine directly change into gas. hence this is sublimation.

condensation is the process where gas is converted into liquid on cooling.

here iodine gas is being converted into droplets on reducing the temperature. hence this is condensation.

The answer in B) sublimation, then condensation.