Chemical reactions

3. New substances formed at the end of a chemical reaction.
5. ______ is a type of chemicals that release hydroxide ion(OH) into an aqueous solution.
6. Bubbling is a sign of ___ being produced.
7. Chemical reactions cannot be undone. That is chemical reactions are ___________.
10. A chemical equation is ______ if there is equal number of each atom on left and right side of the equation.
11. ___ gas will make a pop sound when it is burnt.
15. The reactions that involve burning or explosion is called ______ reaction.
16. A substance that takes part in and undergoes change during a chemical reaction.
17. Reactions that absorb heat is called ____ reactions.
18. An insoluble solid that is formed during a chemical reaction.

1. A chemical reaction where one substance is broken into multiple smaller new substances is called ____ reaction.
2. of mass A law which states that the total mass does not change before and after a chemical reaction.
4. ___ gas will make a glowing splint reignite.
8. _____ gas will make flames go off.
9. ____ is a type of chemicals that release hydrogen ion in an aqueous solution.
12. Reactions that release heat is called ____ reactions.
13. Metal + oxygen gas = metal _________
14. When atoms are separated, ____ is being broken.