Atoms and the Periodic Table

Atom

The basic building blocks of matter, consisting of protons, neutrons, and electrons.

Subatomic Particles

The components of an atom, including protons, neutrons, and electrons.

Proton

A subatomic particle with a positive charge located in the nucleus of an atom, changing the identity of the element.

Neutron

A subatomic particle with a neutral charge located in the nucleus, adding mass and creating isotopes.

Electron

A subatomic particle with a negative charge that orbits outside the nucleus of an atom.

Atomic Number

The number of protons in the nucleus of an atom, determining the element's identity and position on the periodic table.

Atomic Mass

The weighted average mass of an element's isotopes, measured in atomic mass units (amu).

Isotope

Atoms of the same element that have a different number of neutrons.