Question

Why doesn't a small piece of uranium go naturally into a chain reaction?

A) A small piece of uranium is mostly uranium-238. B.) Only large chunks of uranium do this naturally. C.) In a small sample, too small a fraction of neutrons released from each fission are captured to trigger another reaction. D.)Even a small chunk is too large to sustain a chain reaction. E)None of its nuclei fission without bombardment from human-controlled sources.

Answer 1

A- its rate of decay is low ,Uranium-238 has a half-life of an incredible 4.5 billion years. Only when thermal nutreons came it acts