Uranium in its state is found in quantities that average about 4 grammes to every ton of rock. It is an extremely process to extract this mineral, from the rocks that contain it even when the deposits are relatively rich.
The best material for nuclear fission is Uranium 235, but natural uranium has only one atom of this structure for every has been extracted from rocks, the element has to be further processed to get the portion with the atomic structure needed for nuclear reactors.
Once the atomic reaction has been set in motion, the energy which is released mostly takes the form of heat. This heat led to a type of boiler where it generates steam that is later put to several uses. One kilogramme of uranium yields as much energy as 3 million kilogrammes of coal.
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