| A | B |
|---|
| periodic table | an arrangement of the elements in order of their atomic numbers such that elements with similar properties fall in the same column, or group |
| average atomic mass | the weighted average of the masses of all naturally occurring isotopes of an element |
| metalloid | an element that has properties of both metals and nonmetals |
| chemical symbol | a one, two, or three letter abbreviation of the name of an element |
| metal | an element that is shiny and that conducts heat and electricity well |
| group | a vertical column of elements in the periodic table |
| nonmetal | an element that conducts heat and electricity poorly |
| period | in chemistry, a horizontal row of elements in the periodic table |
