Atom Model

Atom Model

An atom is the smallest particle of an element that contains the chemical properties of that element. Learn about atoms and their components (protons, neutrons, and electrons) in this program.

The Atom

The atom is the smallest particle of an element that contains the chemical properties of that element.

The three primary subatomic components of an atom are the proton and neutron (contained in the nucleus), and the electron (orbiting the nucleus at energy levels called shells).

Protons

A proton is a subatomic particle of the nucleus of an atom. Protons have a positive unit charge of one and an atomic mass on one.

The number of protons in the nucleus determines the atomic number and establishes the number of electrons needed to produce an electrically-neutral atom.

Neutrons

A neutron is a subatomic particle of the nucleus of an atom. Neutrons have a neutral unit charge and an atomic mass of one.

Electrons

An electron is a subatomic particle that orbits around the nucleus of an atom in energy levels called shells.

The electron has a negative unit charge and almost no atomic mass.

An atom's chemical properties are established by the distribution and number of electrons in their energy shells.