Question

Which of these is an indication that a chemical reaction has occurred?

A. Freezing of a substance

B. boiling of a substance

C. melting of a substance

D. a change in color of a substance

Answer 1

The answer is D. a change in color of a substance

Just did test

Answer 2

D- If there is a color change that is indicative to that being a chemical change.

A, B, and C are examples of physical changes.