alkali metals
any metal in Group 1A of the periodic table
alkaline earth metals
any metal in Group 2A of the periodic table
halogen
a nonmetal in Group 7A of the periodic table
cation
any atom or group of atoms with a positive charge
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 the atoms are joined
electronegativity
the ability of an atom to attract electrons when the atom is in a compound
inner transition metal
an element in the lanthanide or actinide series; the highest occupied s sublevel and nearby f sublevel of its atoms generally contain electrons; also called inner transition element
ion
an atom or group of atoms that has a positive or negative charge
ionization energy
the energy required to remove an electron from an atom in its gaseous state
metalloid
an element that tends to have properties that are similiar to those of metals and nonmentals
metals
one of a class of elements that are good conductors of heat and electric current; tend to be ductile, malleable, and shiny
nonmetals
an element that tends to be a poor conductor of heat and electric current; nonmetals generally have properties opposite to those of metals
noble gases
an element in group 8A of the periodic table; the s and p sublevels of the highest occupied energy level are filled
periodic law
when the elements are arranged in order of increasing atomic number, there is a periodic repetition of their physical and chemical properties
representative elements
an element in an "A" group in the periodic table; 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 energy level are partially filled
transition metal
one of the Group B elements in which the highest occupied s sublevel and a nearby d sublevel generally contain electrons