| A | B |
|---|
| electron affinity | energy change when an electron is added to an atom |
| electronegativity | tendency of an atom to attract electrons in a chemical bond |
| ionization energy | energy required to remove an electron from anatom |
| period | horizontal row of the periodictable |
| periodic law | a repeating pattern of physical and chemical properties occurs when elements are arranged in order of increasing atomic number |
| atomic radius | one half the distance between nucei in a diatomic element |
| representative elements | elements with partially filled outermost s and p sublevels |
| transition elements | elements with electrons in the outermost s and d sublevels |
| halogens | elements in Group 7 A |
| inner transition elements | elements with electrons in the outermost s and f sublevels |
| noble gases | elements with filled outermost s and p sublevels |
| alkali metals | elements in Group 1A |
| alkaline earth metals | elements in group 2A |
