Nuclear Fission

• What is nuclear fission?

  the process of splitting a large and unstable nuclei
• Where and why is nuclear fission used?

  In nuclear reactors or power plants to produce energy to make electricity
• What are the products of nuclear fission?

  Two smaller daughter nuclei, three neutrons and gamma radiation, as well as lots of energy.
• What is the term used when fission happens randomly?

  Spontaneous fission
• What is induced fission?

  Making the unstable nuclei absorb a neutron
• The energy produced when fission occurs is mostly due to the fission products having a lot of kinetic energy.
• What is a controlled chain reaction?

  When only 1 neutron goes on to make another fission
• What is an uncontrolled chain reaction?

  when all three neutrons go on to cause more fissions
• What are nuclear weapons, such as the atomic bomb, an example of?

  Uncontrolled chain reactions
• What makes an atom bomb explode?

  Two halves of a radioactive nucleus join together to make a critical mass, in order to make nuclear fission occur in an uncontrolled chain reaction.
• What are the four parts of a nuclear reactor core?

  Fuel rods, control rods, moderator and shielding
• What do the fuel rods do?

  They contain uranium, and is where fission takes place.
• What do the control rods do?

  They are lowered into the reactor to absorb neutrons in order to slow down fission
• What does the moderator do?

  it slows down neutrons to make it more likely that the neutrons are absorbed by the nuclei in the fuel rods
• What does the shielding do?

  It surrounds the reactor to stop gamma radiation from escaping
• Why do fuel rods get hotter when they're closer together?

  More neutrons can move from one fuel rod to another causing more fission.
• If a reactor core gets too hot, what should engineers do? How does this control the chain reaction?

  They should lower the control rods so that they absorb the neutrons to prevent them from being absorbed by the uranium to cause a chain reaction.
• Why do some people have concerns about nuclear power?

  Radioactive waste is dangerous and hard to dispose of, and there is also the risk of a nuclear accident