| A | B |
|---|
| atom | smallest particle of a substance |
| proton | positively charged sub-atomic particle |
| neutron | sub-atomic particle w/ no charge |
| electron | negatively charged sub-atomic particle |
| activation energy | necessary to start a chemical reaction |
| catalyst | speeds up a chemical reaction |
| inhibitor | slows down a chemical reaction |
| Groups on the Periodic Table | metals, metalloids, non-metals |
| mass | can't be created or destroyed |
| signs of chemical change | light, heat, color change, new substance |
| precipitate | new solid formed in a reaction |
| bonds break & reform | must happen for a chemical change |
