| Term | Definition |
| Electron Dot Diagram | Diagram of an atom, ion or molecule in which each dot represents a valence electron |
| Ion | An atom or group of atoms that has a positive or negative charge |
| Anion | An ion with a negative charge |
| Cation | An ion with a positive charge |
| Chemical bond | The force that holds atoms or ions together |
| Ionic bond | The force that holds cations and anions together |
| Chemical formula | Notation that shows what elements a compound contains and the ratio of the atoms or ions of these elements in the compounds |
| Crystals | Solids whose particles are arranged in a lattice structure |
| Ionization energy | The amount of energy used to remove an electron from an atom |