| A | B |
|---|
| ion | Atom that is no longer neutral because it has gained or lost an electron. |
| ionic bond | Ions join together in this type of chemical bond. |
| compound | Pure substance that contains two or more elements. |
| covalent bond | Chemical bond that forms when atoms share one or more electrons. |
| molecule | Neutral particle that is formed when atoms share electrons. |
| formula | Combination of chemical symbols that tells what elements are in molecules and how many atoms of each element are present. |
| electron dot diagram | Shows the chemical symbol for an element surrounded by as many dots as there are electrons in its outer energy level. |
| chemical bond | Force that holds two atoms together. |
| electron | A negative particle in an atom. |
| negative ion | A charged atom that has gained one or more electrons. |
| subscript | Represents the number of atoms in a molecule. |
| symbol | One or two letters that represents an element. |
| polar molecule | Particle in which electrons are shared unequally. |
| positive ion | A charged atom that has lost one or more electrons. |
| nucleus | The positively charged center of an atom. |
