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Name: Mary
Status: educator
Location: IL
Country: USA
Date: Spring 2012

What happens to a radioactive isotope when it decays? Does the radioactive material disappear? How or why?


“Isotopes are variants of a particular chemical element. While all isotopes of a given element share the same number of protons, each isotope differs from the others in its number of neutrons."

So if an isotope decays it simply becomes a different chemical element or the same element of a different atomic weight.

Per the above Wikipedia article Uranium Atomic Wt: 238 loses an alpha particle to become Thorium 234 Thorium 234 loses a beta particle to become Protactinium 234 which loses another beta particle to become Uranium 234….and on and on and on.

In the above example of Uranium 238, the radiation part is the alpha, beta and gamma particles that the Uranium, Thorium, Proactinium…lose. These particles just fly off into space, possibly running into a radiation detector.

Sincere regards, Mike Stewart

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