Molecular formula :
nature : Elements of fissile nuclear fission neutrons trigger and emit two to three secondary neutrons, which caused a part of the remaining nuclear fission, the splitting reaction continue constitute a chain reaction. Average generated by the fission neutrons is a secondary cause under a nuclear fission reaction and the chain reaction can sustain itself, the existence of the chain known as fission reaction (criticality). An average of more than one sub-participation of a neutron fission chain reaction called the divergence of fissile reaction (supercritical state). Less than a sub-participation of a neutron reaction finally stopped, known as convergence - fission chain reaction (subcritical state).
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