How does radiation affect the nucleus of an unstable isotope?

1 Answer
Nov 15, 2015

There are three types of radioactive decay, alpha, beta and gamma. Alpha and beta decay both change the nucleus into a different element. Gamma decay simply reduces the energy of the nucleus.

Explanation:

Alpha decay is when a nucleus emits two protons and two neutrons as an alpha particle which is actually a Helium 4 nucleus. The result is that the nucleus which decayed is now has two fewer protons and two fewer neutrons. For example a Uranium 238 nucleus has 92 protons and 146 neutrons. After emitting an alpha particle what is left (the daughter nucleus) is a Thorium 234 nucleus containing 90 protons and 144 neutrons.

Beta decay is when a proton in the nucleus gets converted into a neutron by emitting an electron (or beta particle) and an electron anti-neutrino. For example Carbon 14 has 6 protons and 8 neutrons. After emitting an electron what is left is Nitrogen 14 containing 7 protons and 7 neutrons. The electron anti-neutrino takes away additional binding energy.

Gamma decay is when a nucleus is in an excited state and needs to lose energy. It emits a gamma particle which is a high energy photon. The number of protons and neutrons remains unchanged. A nucleus often undergoes gamma decay after undergoing alpha or beta decay because the daughter nucleus is often left in an excited state.