| A | B |
|---|
| period | Horizontal row of elements in the periodic table whose properties change gradually and predictably. |
| group | Family of elements with similar physical or chemical properties that occupies the same column in the periodic table. |
| metal | Element that is a good conductor of electricity and heat, is usually a solid at room temperature and is shiny, ductile, and malleable. |
| nonmetal | Element that is a poor conductor of heat and electricity and may be a gas or a brittle solid at room temperature. |
| metalloid | Element that shares some properties with metals and some with nonmetals. |
| alloy | Mixture made of two or more elements, one of which is a metal. |
| semiconductor | Element that doesn't conduct electricity as well as a metal but does conduct electricity better than a nonmetal. |
| alkali metals | Elements in Group #1 |
| alkaline earth metals | Elements in Group #2 |
| Boron's family | Elements in Group #13 |
| Carbon group | Elements in Group #14 |
| Nitrogen group | Elements in Group #15 |
| Oxygen's family | Elements in Group #16 |
| The Halogens | Elements in Group #17 |
| The Noble Gases | Elements in Group #18 |
| Iron Triad | Iron, Cobalt, Nickel |
| Coinage Metals | Copper, Silver, Gold |
| Transition elements | Elements in Group 3 through Group 12. |
| Lanthanides | Inner transition elements that are soft metals that can be cut with a knife. |
| Actinides | Inner transition elements that are radioactive. |
