This question is contingent on my understanding of the two terms in the title. As I was taught, a Free Radical is a reactive (high energy?) valence electron released for stability's sake because it is unpaired. I was taught that a Beta Particle is a high energy and fast moving radioactive positron or electron released to stabilize an atom. If both of these premises are true, is there a relation between the two terms, and if so, what is it?

  • 3
    $\begingroup$ Chemistry electrons are ~1eV, betas are ~1keV. $\endgroup$
    – Jon Custer
    Commented Jun 5, 2017 at 18:29
  • 2
    $\begingroup$ A free radical isn't an unpaired electron, it's a species containing one or more unpaired electrons. $\endgroup$ Commented Jun 5, 2017 at 18:56
  • $\begingroup$ Those sound like they should be common names for departmental intramural softball summer league teams - the Free Radicals and the Beta Particles. I'd bet the first is actually pretty common for Chemistry students, the second less so amongst Physics students. $\endgroup$
    – Jon Custer
    Commented Jun 5, 2017 at 22:28
  • $\begingroup$ not directly as most atoms are not radioactive, but indirectly as the electron is energetic enough to form many radicals (and ions) in other molecules. $\endgroup$
    – porphyrin
    Commented Jun 6, 2017 at 8:12

1 Answer 1


There is high-energy in the sense of chemical reactivity, and then there is high energy in the sense of nuclear reactivity. The energy associated with the latter is many orders of magnitude greater than the energy associated with the former, so that there is generally no direct interaction between the two (where the free radical is chemically reactive, and the beta particle arises from nuclear reactivity).

A free radical is a chemical species, whose electron configuration is such that it is highly reactive towards other chemical species. However, this energy is far too low to affect any nuclear reactivity.

A beta particle is a high-energy electron or positron emitted by the radioactive decay of an atomic nucleus. As these particles are emitted from the nucleus of the atom, the electron configuration (i.e. a free radical) is irrelevant; only the stability/reactivity of the nucleus determines whether an atom will emit a beta particle, not the chemical species.

If any of this seems incorrect or unclear, please do not hesitate to ask for clarifications in the comments.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.