- Every element is made up of atoms.

- Atoms are the building blocks of matter.

- Atoms are composed of protons, neutrons, and electrons.

- The nucleus of an atom contains protons and neutrons.

- Electrons orbit the nucleus of an atom.

- When atoms gain or lose electrons, they become ions.

- Chemical reactions involve the rearrangement of atoms.

- Nuclear reactions involve the splitting or fusing of atoms.

- Atom is an ancient Greek word meaning "uncuttable"

- The study of atoms is called atomic physics.