What Affects the Half Life of Caesium?

[GUS]

Caesium has a low melting point but a high evaporation temperature. For this reason it should only be found locally after an accident such as Fukushima . Apart from explosions ejecting particulates high into the atmosphere how else is it that it can be found further afield ?

 

[Astronuc]

Caesium has a low melting point but a high evaporation temperature. For this reason it should only be found locally after an accident such as Fukushima . Apart from explosions ejecting particulates high into the atmosphere how else is it that it can be found further afield ?

It could be carried with the steam and then deposit on dust. Cs-135, Cs-137 and Cs-138 are also decay products of Xe-135, Xe-137 and Xe-138. Xe is a noble gas, so it is readily transportable in air, and once airborne it decays to the corresponding Cs isotope.

See the attached figure. Stable isotopes are not radioactive.

 

[GUS]

It could be carried with the steam and then deposit on dust. Cs-135, Cs-137 and Cs-138 are also decay products of Xe-135, Xe-137 and Xe-138. Xe is a noble gas, so it is readily transportable in air, and once airborne it decays to the corresponding Cs isotope.

See the attached figure. Stable isotopes are not radioactive.

Thanks.

 

[GUS]

It could be carried with the steam and then deposit on dust. Cs-135, Cs-137 and Cs-138 are also decay products of Xe-135, Xe-137 and Xe-138. Xe is a noble gas, so it is readily transportable in air, and once airborne it decays to the corresponding Cs isotope.

See the attached figure. Stable isotopes are not radioactive.

Has this already happened or is possible it will happen at Fukishima ? How much radioctive Caesium is there a portential to be released and what are the potential affects on the globe ?

 

[mathman]

Cs is highly reactive chemically, so it is more like to exist as a salt in a radioactive dust cloud, not as metal.

 

[GUS]

Cs is highly reactive chemically, so it is more like to exist as a salt in a radioactive dust cloud, not as metal.

Once it forms a salt is it still as radiocative ?

 

[Borek]

Once it forms a salt is it still as radiocative ?

Yes, chemistry doesn't matter when it comes to radioactive decay.

 

[GUS]

Yes, chemistry doesn't matter when it comes to radioactive decay.

Is that because its mainly neutron imbalances that form isotopes and neutrons are not relevant to covalent and ionic bonding ?

 

[Calrid]

Is that because its mainly neutron imbalances that form isotopes and neutrons are not relevant to covalent and ionic bonding ?

Yes electromagnetism and the weak force are related, but one doesn't depend on the other in a material per se, well at least beyond the inherent level, ie electro weak unification.

Radiation is the spontaneous emission of a photon or emission by the change from a neutron to a proton or vise a versa with an emission of a +/-nuetrino or +/- e, or the emmision of a helium ion. None of these have anything to do with electrochemical bonding.

Basically electrons in the sense of bonding are not really of any note in nuclear chemistry.

 

[Borek]

Energies involved in electrons/bonding are orders of magnitude lower than those involved in nuclear changes, so - from the point of view of nucleus and nucleons - they are negligible.

I believe there are some specific cases when electron density around nucleus has an observable effect on half life of some isotopes (those reacting by electron capture), but they are pretty rare.

 

[GUS]

Unfortunately I only got to A level physics and Chemistry but basically you are saying that nuclear decay is a property of the nucleus ansd chemical bonding of the electron field around it ? Nonetheless it seems weird to me that the actual element could change due to alph/beta emision but the chemical bond be unaffected. So the name of the compound changes as the nucleus decays through the the different elements ?
So I guess my next question is are any of the things caesium 137 is likely to bond to at Fukushima likely to be gases ?

 

[Calrid]

Unfortunately I only got to A level physics and Chemistry but basically you are saying that nuclear decay is a property of the nucleus ansd chemical bonding of the electron field around it ? Nonetheless it seems weird to me that the actual element could change due to alph/beta emision but the chemical bond be unaffected. So I guess the name of the compound changes as the nucleus decays through the the different elements ?
So I guess my next question is are any of the things caesium 137 is likely to bond to at Fukushima likely to be gases ?

Well actually it has to be both because of the way atoms work, obviously in some forms of decay then the electron shells orbitals will be effected but yes it is unlikely the electrons will be effected directly by nuclear effects. Actually I thought this would be college physics and or chemistry, I suppose it depends on which course you do but I studied beta +/- decay etc at A' level, mine were OU foundation courses though a lot different to A' levels.

I'd hazard a guess not being an expert that most of the contamination would be in the form of solids or particulates in the air due to the nature of the accident and the materials the contaminants are likely to come into contact with at ground level, plus they doused it with gallons of water I seem to remember to try and contain the fission reaction, so probably stacks of contaminated slurry. Anyway just an educated guess.

 

[GUS]

Well actually it has to be both because of the way atoms work, obviously in some forms of decay then the electron shells orbitals will be effected but yes it is unlikely the electrons will be effected directly by nuclear effects. Actually I thought this would be college physics and or chemistry, I suppose it depends on which course you do but I studied beta +/- decay etc at A' level, mine were OU foundation courses though a lot different to A' levels.

It was a loooooong time ago !

 

[Calrid]

It was a loooooong time ago !

Hehe it's cool. I know I don't remember that much from mine and it was 5/6 years ago.

It's also entirely possible that the issues you mention were not really touched on. This isn't a solid application for me at this level either. I'm winging it on some questions.

Hopefully someone with more expertise has better advice. For example I forgot which way round the electron /positron neutrino/antineutrino thing went in beta +/- decay and had to look it up, which is kinda embarrassing. It's all good it refreshed my learning.

 

[Borek]

Unfortunately I only got to A level physics and Chemistry but basically you are saying that nuclear decay is a property of the nucleus ansd chemical bonding of the electron field around it ? Nonetheless it seems weird to me that the actual element could change due to alph/beta emision but the chemical bond be unaffected.

You are only partially right. Once the element changes it is followed by chemical changes of the atom vicinity. However, in most cases (so often you assume it is always) chemical vicinity of an atom doesn't change its half life.

 

[Calrid]

You are only partially right. Once the element changes it is followed by chemical changes of the atom vicinity. However, in most cases (so often you assume it is always) chemical vicinity of an atom doesn't change its half life.

Right that is dependant on an equation that has no regard for variables that include electrons (exceptions you already mentioned).

The half life of a material is dependant on the configuration of the nuclei and configuration alone, not the electron shells for the vast majority of cases where the energy concerns are insignificant in comparison to the forces involved.

I suppose it would be good to say we have to be aware of the electrons and their potential energy ranges, because an atom isn't an energy aggregate that is solely confined to the nucleus. But that such concerns can often be ignored when we produce an overall chemical model of what is going on.