Question

Which of the following is a clue of a chemical change?

a. gas bubbles form in boiling water
b. a gas forms when vinegar and baking soda are mixed
c. balls of wax form when melted wax is poured into ice water
d. iron changes color when heated

Answer 1

C.
Gas forms when vinegar and baking soda are mixed

Answer 2

The best answer is "B". Vinegar and baking soda mixed together is a chemical change.

I hope this helps!
~cupcake