Atom Direct

An atom is the smallest unit of ordinary matter that forms a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. They are incredibly small, typically around 100 picometers across. Atomic Structure Atoms are made of three main subatomic particles: Licensed by Google

: Most of an atom's volume is actually empty space. If an atom were expanded to the size of a football stadium, the nucleus would be the size of a marble in the center, and the electrons would be like tiny gnats buzzing around the highest seats. An atom is the smallest unit of ordinary

: Negatively charged particles that orbit the nucleus in specific regions called shells or orbitals. They are much smaller than protons and neutrons. Key Characteristics Atomic Structure Atoms are made of three main

: Atoms can lose or gain electrons to become ions (charged particles) or vary their number of neutrons to become isotopes of the same element. They are much smaller than protons and neutrons