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General Chemistry

Neutrino

Definition and meaning of Neutrino in chemistry.

Neutrino is a nearly massless, electrically neutral fundamental particle produced in nuclear reactions, particularly in beta decay. Billions of neutrinos pass through Earth and living organisms every second without interacting.

In more detail

Neutrinos are emitted when neutrons decay into protons in radioactive beta-minus decay, alongside electrons. There are three types (flavors) of neutrinos: electron neutrino, muon neutrino, and tau neutrino. Although neutrinos interact only through the weak nuclear force and therefore pass through most matter undetected, they play a crucial role in energy conservation within nuclear reactions. Major natural sources include the Sun through nuclear fusion, radioactive decay of unstable isotopes, cosmic ray interactions with the atmosphere, and nuclear reactors.

Key facts

FieldGeneral Chemistry
Particle symbolnu (ν)
MassExtremely small; best direct experimental upper limit is about 0.8 eV/c² (KATRIN, 2022)
Interaction mechanismWeak nuclear force only
Example

When carbon-14 undergoes beta decay, a neutron converts to a proton, emitting an electron and an electron antineutrino as it transforms to nitrogen-14.

Frequently asked questions

Why don't neutrinos interact with ordinary matter?

Neutrinos interact only through the weak nuclear force, which is exceptionally weak at low energies. Trillions of neutrinos pass through normal matter for every one interaction that occurs.

What are the main sources of neutrinos?

Neutrinos are produced by radioactive decay, the Sun through nuclear fusion, cosmic rays interacting with Earth's atmosphere, and nuclear reactors.