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 solid changing directly into a gas is sublimation. When the iodine gas cooled and changed into liquid droplets, it underwent condensation. Therefore, the processes were sublimation, then condensation, which is choice D.

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