Question

When two substances are mixed together, a color change is observed. Does this mean that a chemical reaction has definitely occurred?

Yes because any change indicates a chemical reaction.
No because some physical changes produce color changes.
No because color changes are not indicators of chemical reactions.
Yes because color changes occur only when new compounds are formed.

Answer 1

I believe its the first one, hope this helps :)

Answer 2

B

Step-by-step explanation:

Because color change also indicates a physical change as well.