halogen
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Argon compounds by decay of chlorine 36
The half life of 36Cl is 301000 years, decaying to stable argon. Is that fast enough to permit spectral identification of unstable argon oxide?
I guess you would obtain the 36Cl by neutron activation of the 1/4 of natural chlorine that is suitable, with or without separation.
Suppose you have a perchlorate salt made with this stuff. Perchlorate anion kicks out an electron. There is now a molecule of ArO4 trapped in this
matrix of perchlorate. What's it going to do? Complain?
There are probably other complex anions of chlorine one might consider, but even the perchlorate anion is only kinetically stable, the oxygen being
crowded around it. All the chlorine oxides are unstable. Maybe argon (VIII) oxide has a barrier to decomposition. Now there would be no earthly way to
purify it, but wouldn't it be nice, to know it existed?
[Edited on 5-10-2015 by halogen]
F. de Lalande and M. Prud'homme showed that a mixture of boric oxide and sodium chloride is decomposed in a stream of dry air or oxygen at a red heat
with the evolution of chlorine.
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annaandherdad
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What is the energy of the emitted electron in this Cl -> Ar decay? If it is reasonably high, you'll get enough recoil of the Ar nucleus to break
any molecular bond, especially one as weak as with oxygen.
I have no idea what this energy is, but in the beta decay of a free neutron the total energy released is about 1.3 MeV, of which 0.5 MeV is taken by
the electron rest mass. The rest is kinetic energy split between the electron and the neutrino. If the electron has a ke of about 0.5 MeV, then I
estimate that the argon atom will recoil with about 10ev energy, certainly enough to break the bond. The electron kinetic energy is probably less
than this, however, so I don't know how the numbers work out.
In any case, the electron from the beta decay will leave quickly, so what is left behind is not a neutral argon atom, but an Ar+ ion. This will
almost certainly have bound states with what is left of the chlorate group (the electron configuration is the same, and the charge will polarize the
other atoms and create an attraction). You won't get neutral argon until a stray electron comes along to neutralize the Ar+. Then the bonds with
the oxygen will break.
Any other SF Bay chemists?
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unionised
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I suspect that you are right, but recoilless emission does happen (not generally with electrons afaik).
https://en.wikipedia.org/wiki/M%C3%B6ssbauer_effect
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