Atomic Structure

All matter is composed of atoms, the smallest individual units of elements. Each atom is made up of three subatomic particles: protons, neutrons, and electrons. Together, these three particles account for the mass and the charge of an atom.

The History of Atomic Theory

The first person to propose that everything on...

Elements are substances with unique physical and chemical properties that cannot be broken down into other substances by chemical reactions.

Each element, like potassium, consists of atoms that differ from those of other elements.

These differences are found in the subatomic particles that make up each atom.

Two of these partic...