Neutron

Definition

A neutron is a subatomic particle found in the nucleus of an atom, possessing no electric charge and a mass slightly greater than that of a proton. Neutrons play a crucial role in the stability of atomic nuclei.

5 Must Know Facts For Your Next Test

1. Neutrons are composed of three quarks: two down quarks and one up quark.
2. The neutron was discovered by James Chadwick in 1932.
3. In nuclear reactions, neutrons can initiate fission or fusion processes.
4. Free neutrons are unstable and decay into protons, electrons, and antineutrinos with a half-life of about 10 minutes.
5. Neutron radiation is a type of ionizing radiation that can penetrate materials more deeply than alpha or beta radiation.

Review Questions

• What is the electric charge of a neutron?
• Who discovered the neutron and in what year?
• What particles result from the decay of a free neutron?

Related terms

Proton:

A positively charged subatomic particle found in the nucleus of an atom.

Quark:

A fundamental constituent of matter that combines to form protons and neutrons.

Beta Decay:

A type of radioactive decay where a neutron transforms into a proton, emitting an electron and an antineutrino.