The major types of Radioactive decay are;

1. Alpha Radiation/Decay alpha particle

During Alpha decay an atom spits out two protons and two neutrons from its nucleus. This little bundle is called an “alpha particle.”

  • Alpha decay usually happens in larger, heavier atoms.
  • The symbol looks like Helium because Helium-4 has the same number of protons and neutrons as an alpha particle (no electrons, though).
  • Since Alpha particles have two protons and no electrons, they have a net charge of 2+.
  • During Alpha radiation an atom’s proton count drops by two, and we know what that means – a NEW element is formed!
  • Alpha radiation can be stopped by PAPER.

NOTE: One of the main sources of alpha particles is the element radon, which is a gas found in many rocks. If a lot of radon is inhaled, it can get in your lungs and damage lung tissue. Some homes are even equipped with radon detectors to warn you if the levels are getting too high.

2. Beta Radiation/Decay beta particle

A neutron is a proton with an electron attached. In beta decay a neutron sends its electron packing, literally ejecting it from the nucleus at high speed. The result? That neutron turns into a proton!

  • Beta decay increases an atom’s electron count by 1 (notice the 1- in the symbol).
  • During Beta radiation an atom’s proton count grows by one. Once again, NEW element!
  • Beta radiation can be stopped by WOOD.

NOTE: Beta emission is when a high speed electron (negative charge) leaves the nucleus. Beta emission occurs in elements with more neutrons than protons, so a neutron splits into a proton and an electron. The proton stays in the nucleus and the electron is emitted.

3. Gamma Radiation/Decay gamma particle

Gamma rays is electromagnetic radiation similar to light. Gamma decay does not change the mass or charge of the atom from which it originates. Gamma is often emitted along with alpha or beta particle ejection.

  • Gamma radiation can be stopped by LEAD.

NOTE: The emission of gamma rays does not alter the number of protons or neutrons in the nucleus but instead has the effect of moving the nucleus from a higher to a lower energy state (unstable to stable). Gamma ray emission frequently follows beta decay, alpha decay, and other nuclear decay processes.