Radioactivity

• What is an isotope?

  An atom with different neutrons
• How does the mass number of an isotope differ from its atomic number?

  Mass number is different, atomic number is normal
• What is a nuclide?

  An element after radioactive decay
• What does a nuclide refer to?

  Different configurations of protons and neutrons
• What is usually released when a nucleus is in an excited state?

  Gamma ray energy
• What is a radiopharmaceutical?

  A nuclide attached to an organic compound
• What is the purpose of a pharmaceutical agent in radiopharmaceuticals?

  To concentrate nuclei in an organ
• For what purposes can radiopharmaceuticals be used?

  Therapeutic and diagnostic purposes
• What does activity refer to in radioactivity?

  Disintegrations per second of unstable nuclei
• What is half-life in radioactivity?

  Time for radioactivity to decay by half
• What is the SI unit for radioactivity?

  Becquerel
• What is radioactivity?

  Emission of radiant energy from decay
• What are the two types of radiation?

  Ionising and nonionising
• What is ionising radiation capable of doing?

  Ionising an atom by ejecting an electron
• What is nonionising radiation unable to do?

  Ionise an atom
• What is cosmic radiation?

  Radiation from the sun and stars
• What is terrestrial radiation?

  Radiation found in soil, water, and vegetation
• What percentage of radiation exposure in the UK is from natural resources?

  85%
• How is radiation used in sterilisation?

  To sterilise plastic containers and meals
• What is radon?

  A radioactive gas from uranium-238 decay
• What does radioactive decay allow an element to achieve?

  Stability by releasing radiation
• What are the parts of an atom?

  Protons, neutrons, and electrons
• What is a stable atom?

  An atom with equal protons and neutrons
• How is mass number calculated?

  Number of protons and neutrons combined
• How is atomic number defined?

  Number of protons in an atom
• How do isotopes and nuclides differ?

  Isotopes have different neutrons, nuclides have energy
• What happens during radioactive decay?

  Nucleus changes energy levels, emitting particles
• What is alpha decay?

  Emission of two protons and two neutrons
• What happens to mass and atomic numbers during alpha decay?

  Mass number reduces by four, atomic by two
• What is beta decay used for?

  Treatment and PET imaging
• What occurs during beta decay?

  A neutron splits into an electron and proton
• What happens to mass and atomic numbers during beta decay?

  Mass number stays the same, atomic increases by one
• What is positron decay?

  A proton turns into a neutron, emitting a positron
• What happens to mass and atomic numbers during positron decay?

  Mass number stays the same, atomic decreases by one
• What is gamma decay used for?

  Imaging
• What is emitted during gamma decay?

  A gamma ray
• What changes occur to atomic and mass numbers during gamma decay?

  No changes occur to atomic or mass numbers
• What is a radioactive decay chain?

  A series of decay events to achieve stability
• What is isometric transition?

  Nucleus moves energy states without changing numbers
• What is Technetium-99m used for?

  In nuclear medicine