Question

Which of the following is an example of a chemical change? (A) iron changing colors when heated (B) gas bubbles forming in boiling water (C) balls of wax forming when melted wax is poured into ice water (D) a gas forming when vinegar and baking soda are mixed

2. A substance that has high reactivity : (A) easily combines chemically with other substances (B) burns in the presence of water (C) displaces dissolved oxygen (D) has a high boiling point


3. If you move a substance from one container to another and it's volume changes, the substance is a: (A) solid (B) liquid (C) gas (D) B&C