Choose a chemical phenomenon: a) dissolution of iodine in alcohol; b) crystallization of salt;

Choose a chemical phenomenon: a) dissolution of iodine in alcohol; b) crystallization of salt; c) rotting of compost; d) boiling milk.

The correct answer is B) rotting of the compost.

Phenomena in chemistry are classified into physical and chemical, depending on the changes that occur with substances. Chemical phenomena include phenomena that entail changes in the chemical composition of a substance, the formation of new substances. The obvious signs of such changes include: discoloration, odor, odor, precipitation, generation or absorption of heat. In the process of rotting compost, the color of the components changes and the smell changes.