Question

After a match has burned which of these is not proof that a chemical reaction occurred?

Answer 1

In my estimation I would say C, I was leaning towards A, but I believe that would merely be "incomplete combustion." I hope this was semi-helpful!

Answer 2

C. i say this because heat and smoke are signs that a chemical reaction is happening. for d if its gone obviously something had to have happened whether it was a chemical or physical reaction so whats left is C.