Idea 3of 7Builds onMass is the fuel
Split the heavy
A slow neutron hits a heavy nucleus. Then?
Today you'll discover
- what one slow neutron can do to a big nucleus
- why one split leads to the next
- what a reactor's control rods are for
Think firstA slow neutron drifts toward a very heavy nucleus
A slow neutron is absorbed by a very heavy nucleus. What happens to it?
Decide first, then press Next. Count what flies out, and where it could go next.
A lone ball arriving at a large cluster of warm and cool balls. After a prediction, the cluster splits into two smaller clusters flying apart, then three single balls leave with rays of energy, then the ledger compares the mass before and after. The last step asks what a reactor's control rods do.
See the whole ideathe big idea and the key word, in one place
The big idea
Fission: a heavy nucleus splits, and lost mass becomes energy.
Where it goes nextOntario's CANDU reactors split uranium this way. The energy boils water to steam, the steam spins a turbine, and the turbine spins the coil that lights the city: the same ledger as every power station, with a nuclear fire at the start.
Key word
- fission
- the splitting of a heavy nucleus into two lighter nuclei, usually triggered by a neutron, releasing energy and more neutrons
About this modelNuclei are drawn a million times too large relative to the atom, and the energy rays are a symbol, not a picture of light.
Nuclei are drawn a million times too large relative to the atom, and the energy rays are a symbol, not a picture of light.
Ready to use it?
- Describe one fission event and explain how a chain reaction is kept steady.