| A | B |
|---|
| Element | Matter that is made of only one kind of atom. |
| Group | Vertical column on the periodic table. |
| Period | Horizontal row on the periodic table. |
| Representative elements | Elements in groups 1-2, and 13-18 on the periodic table and include metals, nonmetals, and metalloids. |
| Transition elements | Elements in groups 3-12 on the periodic table, all of which are metals. |
| Metal | Element that has luster, is malleable, ductile, and is a good conductor of heat and electricity. |
| Nonmetal | Element that is usually a gas or brittle solid at room temperature and is a poor conductor of heat and electricity. |
| Metalloid | Element that shares some properties of both metals and nonmetals. |
| Alkali Metals | Group 1 on the periodic table that has 1 valence electron. |
| Alkaline Earth Metals | Elements in group 2 on the periodic table that have 2 valence electrons. |
| Boron Family | Elements in group 13 on the periodic table that have 3 valence electrons. |
| Carbon Family | Elements in group 14 on the periodic table that have 4 valence electrons. |
| Nitrogen Family | Elements in group 15 on the periodic table that have 5 valence electrons. |
| Oxygen Family | Elements in group 16 on the periodic table that have 6 valence electrons. |
| Halogen Family | Elements in group 17 on the periodic table that have 7 valence electrons |
| Noble Gas | Elements in group 18 on the periodic table that have 8 valence electrons except helium that has 2 |
| Inner Transition Elements | The two rows located at the bottom the the periodic table that include the lanthanide and actinide series. |
| Lanthanide Series | 1st row of the inner transition elements |
| Actinide Series | 2nd row of the inner transition elements |
| Valence Electrons | Electrons in the outermost energy level of an atom |
| Periodic Table | Is a system of classifying and logically grouping all known elements |
| Semi Conductor | Are elements that do not conduct electricity as well as a metal but better than a nonmetal. |
| Synthetic Element | Elements that are man made in laboratories and nuclear reactors. |
| Atomic Number | The number of protons in the nucleus of an atom. |
| Chemical Symbol | Is a 1 or 2 letter symbol used to represent elements. |
| Atomic Mass | The weighted avg mass of all existing atoms of an element. |
| Isotope | Is an atom of an element with a different number of nuetrons than normal. |
| mass Number | The sum of protons and neutrons in the nuclues of an atom. |
