Question

Which evidence is an indication that a chemical reaction has occurred?

Responses

freezing of a substance

freezing of a substance

formation of a precipitate

formation of a precipitate

melting of a substance

melting of a substance

boiling of a substance

Answer 1

The formation of a precipitate is an indication that a chemical reaction has occurred. Precipitation typically results from a chemical reaction between substances in a solution, leading to the formation of an insoluble solid. The freezing, melting, and boiling of a substance are physical changes and do not necessarily indicate a chemical reaction.

Answer 2

choose one of the answer choices above

Answer 3

The correct answer is **formation of a precipitate.**