6.2.2 - Nuclear Fission Flashcards
What is nuclear fission?
When a large nucleus splits into fragments and emits neutrons.
Does nuclear fission happen spontaneously?
Not often.
When is nuclear fission much more likely to happen?
If a nucleus absorbs a neutron.
What happens to the nucleus in nuclear fission?
Splits and produces two smaller nuclei, and two or three neutrons.
What may happen to the smaller nuclei produced?
Be unstable and decay.
What are two examples of atoms that are easily fissionable?
- Uranium-235.
2. Uranium-239.
What does fissionable mean?
They can be split easily.
What happens as the fission products are moving?
They collide with, and heat up the matter around them.
Where can you use the fission process?
In a nuclear power station.
How can you use the fission process in a power station?
To heat water to produce steam to drive turbines and generators.
What are some other uses for the fission process?
To power a nuclear submarine or spacecraft.
Compare the energy transferred to the surroundings in a fission reaction to the energy transferred to the surroundings in a combustion reaction?
Thousands times more.
What do you need to start a fission reaction?
A neutron.
How does the fission process become a chain reaction?
Because the process produces neutrons, which trigger other fission reactions.
In a nuclear power station, how many fissions happen in a second?
Billions, so a huge amount of energy is released.
