is an arrangement of elements in columns, based on a set of properties that repeat from row to row.
is a row in a periodic table of elements.
is a column of elements in a periodic table.
is the pattern of repeating properties displayed by elements in the periodic table.
Atomic Mass Unit (AMU)
is one-twelfth the mass of a carbon-12 atom.
are elements that are good conductors of heat and electric current.
are elements that form a bridge between elements on the left and right sides of the periodic table.
are elements that are poor conductors of heat and electron current.
are elements with properties that fall between those of metals and nonmetals.
is an electron that is in the highest occupied energy level of an atom.
are the elements in Group 1A of the periodic table, not including hydrogen.
Alkaline Earth Metals
are the elements in Group 2A of the periodic table.
are the elements in Group 7A of the periodic table.
are the elements in Group 8A of the periodic table.
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