| A | B |
|---|
| chemical bond | the force that holds two atoms together |
| chemical formula | combination of chemical symbols and numbers that shows which elements are present in a compound |
| compound | pure substance containing two or more elements |
| covalent bond | chemical bond that forms between two nonmetal atoms when they share electrons |
| electron cloud | area of space around the nucleus where electrons travel |
| electron dot diagram | the symbol for the element surrounded by as mnay dots as there are electrons in its outer energy level; only the outer level are shown |
| energy level | different areas for electrons in an atom; each level represents a different amount of energy |
| ion | an atom that is no longer neutral becasue it gained or lost an electron |
| ionic bond | when a positive ion and a negative ion are strongly attracted to each other; is a type of chemical bond |
| metallic bond | formed when metal atoms share their pooled electrons |
| molecule | neutral particle formed when atoms share electrons |
| polar bond | bond in which electrons are shared unevenly |
