A row in the periodic table is called __________.
a period
One twelfth the mass of a carbon-12 atom.
atomic mass
Elements that are poor conductors of heat and electric current.
Nonmetals
Elements that are good conductors of heat and electric currents.
metals
The pattern of repeating properties displayed by elements in the periodic table.
Periodic Law
Elements that form a bridge between elements on the left and right sides of the periodic table.
Transition metals
valence electron
A column of elements in a periodic table.
Group
Elements with properties that fall between those of metals and nonmetals.
metalloids
Elements that have a single valence electron, are extremely reactive, and are in Group 1A.
Alkali metals
An arrangement of elements in columns, that repeat from row to row.
Periodic Table
These elements have 8 valence electrons and are located in group 8A.
Noble gases
The elements in Group 7A on the periodic table and have 7 valence electrons.
Halogens
These elements have 2 valence electrons and are located in Group 2A.
Alkaline earth metals