Formation of a precipitate is usually evidence of?
the separation of a mixture, a chemical change, formation of a mixture, physical change

Formation of precipitate is usually an evidence of a chemical change. The precipitate is a new substance that gets created due a chemical reaction between two or more different substances.  The precipitate can be the formation of a solid within a liquid or the formation of a solid within a solid due to a chemical reaction or change. The solid formation within a liquid is known as precipitate. This kind of chemical reaction can be seen in normal and daily life, as well as in laboratories.

What are you trying to ask?

Ibelieve the answer is b