An element is a substance that is made up of a single kind
of atom, the building blocks of matter. It is a substance that consists
of atoms with the same number of protons or atomic number. It is a material
which cannot be changed into another form nor broken down. Examples of elements are Oxygen, carbon, Mercury,
and many others. There are about 117-118
known elements.
You can see the atomic number, atomic weight, and other information about certain
elements on the periodic table.
