Question

Which scenarios are definite signs that a chemical reaction has occurred?
_(Select all that apply)_

Water is heated and releases a gas.
Blue and yellow paint mix to make green paint.
A piece of iron begins to rust.
Two liquids are mixed together and release a light.

A and C?

Answer 1

yes

Answer 2

Thank you! :)

Answer 3

umm ... boiling water releases a gas , no chemical reaction
... dissolved gases come out of solution , then the water goes to steam

a release of light indicates an energy change
... powered by a reaction

Answer 4

I interpreted A this way. A chemical reaction produces heat which boils the water enough to produce steam. The production of heat shows the presence of a chemical reaction.

I agree with D as yes.