Describe the three particles of radioactive decay.

1. Alpha Particle: The alpha particle is a positively charged particle that is actually a helium nucleus consisting of two protons and two neutrons. Alpha particles typically have a range of only a few inches in air, are easily stopped by a sheet of paper and do not penetrate the outer layer of dead skin cells, making them relatively unlikely to damage living tissue. Alpha particles are released during the alpha decay of a heavy radioactive element and the emission of an alpha particle in a nuclear reaction generally identifies the reaction as having been an alpha decay. 2. Beta Particles: Beta particles are a type of ionizing radiation consisting of high-energy, high-speed electrons or positrons emitted from the nucleus of an atom during beta decay. Beta particles have a much longer range of several feet in air, causing significantly greater damage to tissue as they travel through it. Though less damaging than alpha particles, beta particles still pose a health risk and require protective shielding. 3. Gamma Rays: Gamma rays are a form of electromagnetic radiation that generally has the highest energy of the three types of radiation. Unlike alpha and beta particles, gamma rays can travel for great distances in air and through most substances, including the human body. Thus, gamma rays can be particularly dangerous, as they can penetrate deep into living tissue, depositing their energy and potentially causing significant damage. Gamma rays are produced during gamma decay, and are often used in medical imaging and other forms of radiation therapy.