| A | B |
|---|
| cation | positive ion |
| anion | negative ion |
| ion | atom with a charge |
| valence electrons | electrons in highest energy level |
| +1 | charge of Group 1 |
| +2 | charge of Group 2 |
| +3 | charge of Group 13 |
| -3 | charge of Group 15 |
| -2 | charge of Group 16 |
| -1 | charge of Group 17 |
| Noble Gases | least reactive group |
| Alkali Metals | most reactive metals |
| Halogens | most reactive nonmetals |
| 1 | valence electrons in Group 1 |
| 2 | valence electrons in Group 2 |
| 3 | valence electrons in Group 13 |
| 5 | valence electrons in Group 15 |
| 6 | valence electrons in Group 16 |
| 7 | valence electrons in Group 17 |
| 8 | valence electrons in Group 18 |
