Vocabulary # 3 Chemical Changes

1. Compound: A chemical combination of two or more elements

2. Chemical bond: A link that atoms or electrically charged particles can form with each other

3. Chemical formula: a way of using letters and numbers to show how much of each element is in a substance.

4. Ion: An electrically charged particle with unequal numbers of protons and electrons.

5. Molecule: A group of bonded atoms that acts like a single particle

6. Chemical property: A way of describing how a substance changes chemically with other substances.

7. Exothermic: A reaction that gives off heat

8. Endothermic: A reaction that absorbs heat