atoms and nuclear radiation

Cards (96)

  • What are isotopes?
    Atoms of the same element with different neutrons
  • What makes carbon-14 a radioactive isotope?
    It has an unstable nucleus
  • What happens to the nucleus during radioactive decay?
    The nucleus gives out radiation
  • What is the purpose of radioactive decay?
    To become stable
  • What kind of process is radioactive decay?
    A completely random process
  • What is activity?
    Rate at which nuclei decay
  • What unit is activity measured in?
    Becquerel (Bq)
  • What does one Becquerel equal?
    1 decay per second
  • What device is used to measure the activity of a radioactive source?
    A Geiger-Muller tube
  • What is the count rate?
    Number of decays recorded each second
  • What are the four different types of radiation that can be emitted by an unstable nucleus?
    • Alpha particle
    • Beta particle
    • Gamma ray
    • Neutron
  • What does an alpha particle consist of?
    Two protons and two neutrons
  • Why is count rate not the same as activity?
    Due to background radiation
  • What is an alpha particle the same as?
    The nucleus of a helium atom
  • What is a beta particle?
    An electron ejected from the nucleus
  • Where does a beta particle come from?
    Formed inside the nucleus
  • How is a beta particle formed?
    Neutron changes into a proton and electron
  • What type of radiation is a gamma ray?
    Electromagnetic radiation
  • What is the fourth type of radiation sometimes given out by an unstable nucleus?
    A neutron
  • What does it mean for an isotope to be radioactive?
    Its nuclei decay and release radiation
  • Why is radioactive decay described as a random process?
    Because we cannot predict when it will happen
  • Approximately how far can alpha particles travel in air?
    Around 5 cm
  • What are the three types of radiation discussed?
    Alpha particles, beta particles, and gamma radiation
  • Why do alpha particles have a short range in air?
    They are large and collide with air particles
  • Approximately how far can beta particles travel in air?
    Around 15 cm
  • What material is required to stop alpha particles?
    A single sheet of paper
  • How far can gamma radiation travel in air before stopping?
    Several meters
  • What material is needed to stop beta particles?
    A few millimeters of aluminium
  • What type of material is required to stop gamma radiation?
    Several centimeters of lead
  • What are ions?
    Atoms with a charge
  • What process can radiation cause when it collides with atoms?
    Atoms lose electrons and form ions
  • How strongly ionizing are alpha particles?
    Very strongly ionizing
  • How strongly ionizing are beta particles?
    Quite strongly ionizing
  • How does the ionizing power of beta particles compare to alpha particles?
    Beta particles are not as ionizing
  • How strongly ionizing is gamma radiation?
    Only weakly ionizing
  • What does a nuclear equation show?
    What is produced when a radioactive nucleus decays
  • What particles are contained within an alpha particle?
    Two protons and two neutrons
  • What is an alpha particle identical to?
    The nucleus of a helium atom
  • How is an alpha particle represented by scientists?
    By using the symbol for helium
  • What does the atomic number of 2 on the helium symbol tell us about an alpha particle?
    It contains two protons