Alkali metals
any metal in group 1A of the periodic table
Alkaline Earth Metals
any metal in group 2A of the periodic table
anion
any atom or group of atoms with a negative charge
atomic radius
one half the distance between the nuclei of two atoms of the same element when atoms are joined
cation
any atom or group of atoms with a positive charge
electro-negativity
the ability of an atom to attract electrons when the atom is in a compound
halogens
a nonmetal in group 7A of the periodic table
inner-transition metal
an element in the actinide series; highest occupied "s" sublevel and nearby "f" sublevel of its atoms generally contain electrons
ion
an atom or group of atoms with a positive or negative charge
ionization energy
energy required to remove an electron from an atom in its gaseous state
metalloid
an element that tends to have properties that are similar to most of metals and nonmetals
metal
one of a class of elements that are good conductors of heat and electric current; metals tend to be ductile, malleable, and shiny
noble gas
an element in Group 8A of the periodic table; the s and p sublevels of the highest occupied energy level are filled
nonmetal
an element that tends to be a poor conductor of heat and electric current; nonmetals generally have properties opposite those of metals
periodic law
when elements are arranged in order of increasing atomic number there is a periodic repetition of their physical and chemical properties
transition metal
one of the group b elements in which the highest occupied s sublevel and nearby d sublevel generally contain electrons
representative elements
an element in our A group in the periodic table; and as a group these elements display a wide range of physical and chemical properties. In their atoms, the s and p sublevels in the highest occupied s energy levels are partially filled