element note cards

Element: A pure substance made up of only one kind of atom that can not be
broken down into a simpler form.

Chemical Symbol: a representation of the name of an element that consists of
one or two letters.

Periodic Table: A chart of all the known elements found on this earth which Dmitri
Mendeleev first developed in 1869.

Groups: The 18 vertical columns of elements on the table that organizes them into
families with similar chemical properties. The atoms of elements within a
group all have equal numbers of valence electrons.

Periods: The 7 horizontal rows of elements that show how the chemical properties
slowly change as you move across from one element to another. The
atomic number of the elements increases by one, therefore the electron
number increases as well.