Alpha (a) Particle
| Formula / Notation | ⁴₂He (2 protons + 2 neutrons) |
|---|---|
| Also Known As | Alpha radiation, helium-4 nucleus, α-particle |
What is Alpha (a) Particle?
An alpha particle is a helium-4 nucleus consisting of two protons and two neutrons, emitted during alpha decay of radioactive nuclei. With a charge of +2 and relatively large mass, alpha particles have low penetrating power but high ionising ability, and are stopped by a sheet of paper or a few centimetres of air.
Formula & Notation
Other Names / Synonyms: Alpha radiation, helium-4 nucleus, α-particle
Properties & Characteristics
Uses & Applications
Safety Information
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
Key Facts
Frequently Asked Questions
An alpha particle is a helium-4 nucleus consisting of two protons and two neutrons, emitted during alpha decay of radioactive nuclei. With a charge of +2 and relatively large mass, alpha particles have low penetrating power but high ionising ability, and are stopped by a sheet of paper or a few centimetres of air.
Alpha particles are used in smoke detectors (americium-241 sources), in cancer treatment via targeted alpha therapy (TAT), and in nuclear physics research to probe atomic structure. Ernest Rutherford used alpha particles in his famous gold-foil experiment to discover the atomic nucleus.
Alpha particles are not hazardous as external radiation sources since they cannot penetrate skin. However, if alpha-emitting material is inhaled, ingested, or enters a wound, it poses a severe internal radiation hazard due to high linear energy transfer.
The formula or notation for Alpha (a) Particle is: ⁴₂He (2 protons + 2 neutrons)