1. A radioactive isotope is an atom that has a nucleus that is not stable (will change to form a nucleus of a different element). The process by which the nucleus changes to form another nucleus is called radioactive decay. During radioactive decay a nucleus will give off radiation (waves or particles emitted from the nucleus of a radioisotope). 25.1 Nuclear Radiation

2. The three main types of nuclear radiation are alpha radiation, beta radiation, and gamma radiation. Alpha Particle (2 protons & 2 neutrons) a.k.a. Helium Nucleus Beta Particle (electron) Gamma Ray (high energy radiation) 25.1 Types of Radiation

3. Alpha Radiation (2 protons & 2 neutrons) When an atom loses an alpha particle, the atomic number of the product atom is lower by two and its mass number is lower by four. Can cause damage to soft tissue. Should not be ingested. 25.1 Types of Radiation Nuclear Equation: 94 Pu  92 U + 2 He 240 236 4

4. Beta Radiation An electron resulting from the breaking apart of a neutron in an atom. The neutron breaks apart into a proton, which remains in the nucleus, and a fast moving electron, which is released. 25.1 Types of Radiation Nuclear Equation: 88 Ra  89 Ac + -1 e 228 228 0

5. Gamma Radiation A high energy photon (electromagnetic radiation). Often emitted during beta and alpha decay. Emission does not alter the atomic number or mass number of the atom. Extremely penetrating. 25.1 Types of Radiation