The reaction that takes place in a nuclear fission reactor is as follows: 235/92 U + 1/0n 94/36Kr + 139/56 Ba + 3/0n.
A nuclear fission reactor is the place where nuclear chain reactions occur that produce energy by fission.
Nuclear fission is the nuclear reaction in which a large nucleus splits into smaller ones with the simultaneous release of energy.
Therefore, the option that involves the splitting of atoms into smaller ones is as follows: 235/92 U + 1/0n 94/36Kr + 139/56 Ba + 3/0n.
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