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.
Please allow access to your computer’s microphone to use Voice Recording.
We can’t access your microphone!
Click the icon above to update your browser permissions above and try again
Reload the page to try again!
Press Cmd-0 to reset your zoom
Press Ctrl-0 to reset your zoom
It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.
Your microphone is muted
For help fixing this issue, see this FAQ.