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Radioactive series
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Chains of successive decays.
Heavy nuclei decay through chains of alpha and beta steps to stable lead (uranium, thorium and actinium series). Daughter products can be in secular equilibrium with the parent.
Radon gas comes from the uranium-238 series.
Four series by mass number 4n, 4n+1, 4n+2, 4n+3.
In more detail
Radioactive decay series are chains in which a parent nucleus decays to a daughter, which then decays to other nuclei until a stable one is reached. Uranium, thorium and actinium each form such series.
Real-world uses
- Decay chains are used in radon monitoring and geological dating.
- Understanding chains helps with waste management.
- Physicists study the decay chains of uranium and thorium, which give natural background radiation in rocks.
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Frequently asked questions
How many series are there?
Naturally occurring series include the uranium, thorium and actinium chains.
Where does the chain end?
At a stable isotope of lead for the uranium and thorium series.
What is a radioactive series?
A chain in which each nucleus decays into the next, until a stable isotope is reached.
Related topics in Atomic & Nuclear Physics
Half-life · Mean life · Activity · Carbon dating · Nuclear reactions · Q-value