Chemistry vocab

4. Reaction where parts of two ionic compounds are exchanged, producing two new compounds.
6. Principle stating that matter cannot be created or destroyed in a chemical reaction.
13. Reaction: Process that leads to the transformation of one set of chemical substances to another.
14. Reaction that releases energy, usually in the form of heat.
15. Reaction where two or more simple substances combine to form a more complex one.
18. Substance that starts a chemical reaction.
19. Change that results in the formation of new chemical substances.

1. Observable signs that a chemical change has occurred, such as gas production or color change.
2. Reaction that absorbs energy from its surroundings.
3. Reaction where one element replaces another element in a compound.
5. Change in the form of a substance but not its chemical composition.
7. Chemical equation where the number of atoms of each element is the same on both sides of the equation.
8. Substance formed in a chemical reaction.
9. Substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.
10. Rapid reaction between a substance with an oxidant, usually oxygen, to produce heat and light.
11. Solid that forms in a liquid solution during a chemical reaction.
12. Reaction: Reaction where a single compound breaks down into two or more simpler substances.
16. Number placed in front of a chemical formula to balance an equation.
17. Number written below and to the right of a chemical symbol indicating the number of atoms.