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Specialty Chemistry Forums => Nuclear Chemistry and Radiochemistry Forum => Topic started by: xanthocyanopia on April 19, 2006, 04:55:27 PM

Title: Beta Decay
Post by: xanthocyanopia on April 19, 2006, 04:55:27 PM

I don't quite understand the process of beta decay...

I get that a neutron is converted into a proton, electron and neutrino...and the electron is ejected from the nucleus as a "high energy electron" (beta particle)

My question is why doesn't the atom become positively charged?  Before it was neutral, now it has one more proton than it started with, so how can the charge be neutral?

Thanks

Title: Re: Beta Decay
Post by: Borek on April 19, 2006, 05:23:22 PM

You are right - at first atom becomes positively charged. Then - depending on circumstances - it may also loose one of the valence electrons and get neutral. But as it is atom of completely different element strange things may happen. Imagine you are dancing with your girlfriend and lo - she changes to her neighbour on the student list :) That's more or less what happens in particle where beta decay takes place :)

Title: Re: Beta Decay
Post by: xanthocyanopia on April 19, 2006, 07:34:34 PM

If the atom becomes positively charged and loses a valence electron, wouldn't that make it a +2 charge?

Title: Re: Beta Decay
Post by: Borek on April 20, 2006, 04:16:53 AM

Thinking typo :)

Title: Re: Beta Decay
Post by: jdurg on April 22, 2006, 08:31:41 PM

Yes, the atom formed does take on the positive charge initially, but the beta particle it gives off doesn't remain free indefinitely.  As it hits things, the beta particle knocks off valence electrons hence why it is considered "ionizing" radiation.  After some time, it will slow down enough that a positively charged atom will pick up the electron and after a short while all the charges balance out and the newly formed isotope will wind up as a neutral atom.