IONIZING RADIATION FROM THE NUCLEUS

• An unstable nucleus can become more stable over time by randomly emitting ionizing radiation. This process is called radioactive decay.
• -An alpha particle consists of two neutrons and two protons.

  -A beta particle is a high speed electron ejected from the nucleus when a neutron turns into a proton.

  -Gamma radiation is electromagnetic radiation from the nucleus.
• 4 0 0

  a B V

  2 -1 0
• -Alpha particles are the most ionizing, the least penetrating (cant through paper), and has 5cm range in air.

  -Beta is moderately ionizing, moderately penetrating (cant through 5mm aluminum, 2mm lead), 1m range in air.

  -Gamma is the least ionizing, and most penetrating (cant through thick lead, 1m concrete), range in air is unlimited.
• the activity of a radioactive substance is the number of atoms of that substance that decay per second.
• half-life is the time for the initial count rate of an isotope to halve.
• specific times of nucleus decay cannot be predicted, but the number of nuclei that will decay in a given time can.