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Author Topic: Can inner electron shells participate in chemical reactions?  (Read 3255 times)

Offline Atomic-S

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It has been found that "inert" gases having large atomic masses, such as xenon, can 

form compounts with strong oxidizing elements. Apparently, in these elements the outer

shell, although complete, is far enough removed from the nucleus that some of its

electrons can be removed by a strongly electronegative element.

Raising the following question: What happens if the atomic number is increased by one,

and the experiment repeated? I.e., instead of xenon, we would use cesium, which is, of

course, a monovalent alkaline metal one atomic number greater than xenon. Ordinarily

cesium is thought of as being the kind of thing that, with halogens, will form salts (as

CsCl), or with oxygen, alkalies (as Cs2O) . These combinations strip off the

outer electron, leaving a complete underlying shell like that of an inert gas. That

shell, of course, will be held a bit tighter than in an inert gas because the nuclear

charge is now one greater than in the gas; however, because the atomic number is large,

the total force with which the electrons are held may still be relatively modest. Can,

therefore, electrons be extracted from it by additional applications of strongly

oxidizing elements? For example, CsF might be coaxed to become CsF3 or maybe

even CsF5. Undoubtedly, such a compound, if it can be formed, would be much

different than the salt CsF, dipping, as it does, into electrons which are much more

difficult to remove than the single ordinary valence electron.


 

Offline Bored chemist

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Can inner electron shells participate in chemical reactions?
« Reply #1 on: 27/10/2009 19:30:31 »
It's difficult to strip the first electron from Xenon- not many things can do it and the compounds are not very stable.
It's roughly twice as hard to strip the second electron from Cs: nothing is going to do that and form a stable compound. (the ionisation potentails are 12.13 and 25.1 Volts respectively).

However it's possible that in an electrical discharge in a gas you could get some odd looking compounds like CsF2
 

Offline Atomic-S

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Can inner electron shells participate in chemical reactions?
« Reply #2 on: 29/10/2009 23:14:44 »
Which I assume would be unstable. What if we went to Fr instead of Cs?
 

Offline Bored chemist

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Can inner electron shells participate in chemical reactions?
« Reply #3 on: 30/10/2009 19:55:10 »
It depends on your definition of "stable". Since Francium itself isn't stable- the longest lived isotope has a half life of about 22 min none of it's compounds would be stable.
If you ignore the radioactive decay then I still doubt that you could get a stable compound in an oxidation state higher than 1.
I very much doubt anyone has tried.
However ther have been some experiments on the vapourised metal. The spectroscopic properties might give an indication of the 2nd ionisation potential. If that's low enough then it might give Fr(II) compounds.
 

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Can inner electron shells participate in chemical reactions?
« Reply #3 on: 30/10/2009 19:55:10 »

 

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