Nuclear decay and energy

• What is nuclear fission?

  Splitting of a radioactive nucleus to release energy
• What results from high-energy collisions between light nuclei?

  Fusion, which releases energy
• What is the central part of an atom called?

  • Nucleus
  • Contains protons and neutrons
  • Has most of the atom's mass
• What is the plural of nucleus?

  Nuclei
• What is the process of splitting a nucleus called?

  Nuclear fission
• What is another word for fission?

  Splitting
• What can induce fission in particular nuclei?

  Absorption of slow neutrons
• What are fissile nuclei?

  Nuclei that can undergo fission
• What happens when neutrons emitted from fission collide with other nuclei?

  They can lead to a sustainable chain reaction
• What happens if neutrons are moving too fast?

  Fission will not occur
• Which isotopes are commonly used as fuel in nuclear reactors?

  Uranium or plutonium isotopes
• Why are uranium and plutonium isotopes used in reactors?

  Their large nuclei are easy to split
• What occurs when a uranium-235 nucleus is hit by a neutron?

  The nucleus splits into two smaller nuclei
• What are the smaller nuclei produced from fission called?

  Daughter nuclei
• What is released during the fission process?

  Energy and additional neutrons
• What is a chain reaction in nuclear fission?

  Neutrons released cause more nuclei to split
• How is the chain reaction controlled in nuclear reactors?

  To stop it moving too quickly
• What happens to many fission products?

  They are radioactive and decay
• What is the half-life of Technetium-99?

  211,100 years
• How is half-life defined?

  Time for nuclei to halve in a sample
• What can vary among fission products?

  Half-lives
• What is the half-life of some fission products?

  About 5 years
• What is nuclear fission?

  Splitting of a radioactive nucleus to release energy
• What results from high-energy collisions between light nuclei?

  Fusion, which releases energy
• How do nuclear reactors generate power?

  • Heat from nuclear reactions boils water
  • Steam spins a turbine
  • Turbine turns a generator
• How do nuclear power stations differ from conventional power stations regarding carbon dioxide emissions?

  Nuclear power stations do not release carbon dioxide
• What are the common nuclear fuels used in reactors?

  Uranium and uranium oxide
• Why are uranium and uranium oxide considered non-renewable resources?

  Their supplies are limited
• What is ionising radiation?

  Radiation that removes electrons from atoms
• Why is it important to prevent ionising radiation from escaping a reactor?

  It can cause cancer
• What is a consequence of the waste from nuclear power stations?

  It is radioactive and harmful
• What is plutonium in the context of nuclear reactors?

  A waste product that can make bombs
• What are the key components of a nuclear reactor's containment system?

  • Steel walls
  • Concrete walls
  • Prevents radiation escape
• What is nuclear fission?

  The splitting of a radioactive nucleus
• What does nuclear fusion result in?

  Release of energy from light nuclei
• What is required to control nuclear reactions in power stations?

  • Control rods
  • Moderator (usually water)
  • Neutron-absorbing materials
• What is the role of control rods in a nuclear reactor?

  To control the rate of nuclear reaction
• What materials are commonly used for control rods?

  Boron and other neutron-absorbing materials
• How does the movement of control rods affect the nuclear reaction?

  Moving down slows the reaction, moving up speeds it
• What happens to neutrons after a collision in a nuclear reactor?

  Only one neutron is allowed to collide