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Name:   naz
Status:   student
Age:   16
Location: N/A
Country: N/A
Date: 2000-2001

Describe how commercial radioisotopes are produced in nuclear reactors

Isotopes are elements with the same number of protons, but different neutron counts. One way to make a radioisotope is to bombard atoms with a stream of neutrons. Some of the neutrons join the atoms. If an atom gets too many neutrons, it becomes unstable. This is a radioactive isotope. When these radioactive isotopes decay into smaller elements, often the products are also radioactive.


You stick a sample into the neutron flux in the reactor, and nuclei in the sample get activated when a neutron enters them. In principle, the cleanest activation should occur if the neutrons hitting the sample have the optimal energy to take the sample nuclei through the chain that maximizes the amount of the desired isotope and minimizes the amounts of unwanted isotopes. I don't know how well this optimization works in practice, or even if it is routinely attempted.

Tim Mooney

I suggest trying your local library and looking up 'radioisotopes' and/or 'nuclear reators' to find your answer. Good luck.

Katie Page

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