| A | B |
|---|
| chemical formula | shows the kinds and numbers of atoms in the smallest representative unit of a substance |
| valence electrons | electrons in the highest occupied energy level of an element's atoms |
| electron dot structure | a diagram that shows valence electrons as dots |
| octet rule | In forming compounds, atoms tend to react so as to acquire the stable electron configuration of a noble gas |
| halide ion | a negative ion formed when a halogen atom gains an electron |
| formula unit | the lowest whole-number ratio of ions in an ionic compound |
| ionic bonds | the electrostatic attraction that binds oppositely charged ions together |
| coordination number | the number of ions of opposite charge that surround the ion in a crystal |
| metallic bonds | the attraction of free- floating valence electrons for positively charged metal ions |
| ionic compounds | compounds composed of cations and anions |
| alloy | a mixture of two or more elements, at least one of which is a metal |
| anions | negatively charged ions |
| cations | positively charged ions |
