Plutonium

[hazelm]

A new form of plutonium - solid and stable - found.

 

https://www.sciencedaily.com/releases/2019/10/191018112143.htm

[exchemist]

A new form of plutonium - solid and stable - found.

 

https://www.sciencedaily.com/releases/2019/10/191018112143.htm

Pu in oxidation state +5 is referred to in my 1970s era inorganic chemistry textbook,  so there seems to be something missing in this article. Pu (V) is not new! 

 

What the textbook does say, however is that Pu (V) often seems to disproportionate*, for example to Pu (VI), Pu (IV)  and Pu(III). So what may be new is a stable Pu(V) compound in the solid state, which is what is described in the small print.

 

* Disproportionation is when a compound contains an element that can exist in a variety of oxidation states, and the higher and lower states are more stable than one in between. A compound formed from the intermediate oxidation state will then tend to decompose, to yield 2 or more different compounds, ones in which the element is present instead in these more stable oxidation states. 

 

A simple example is mercurous chloride, Hg2Cl2, which tends to decompose into a mixture of mercury metal, Hg, and mercuric chloride, HgCL2. Two atoms of Hg in the +1 oxidation state turn into one in the zero oxidation state (the element itself) and one with oxidation state +2. 

[hazelm]

Pu in oxidation state +5 is referred to in my 1970s era inorganic chemistry textbook,  so there seems to be something missing in this article. Pu (V) is not new! 

 

What the textbook does say, however is that Pu (V) often seems to disproportionate*, for example to Pu (VI), Pu (IV)  and Pu(III). So what may be new is a stable Pu(V) compound in the solid state, which is what is described in the small print.

 

* Disproportionation is when a compound contains an element that can exist in a variety of oxidation states, and the higher and lower states are more stable than one in between. A compound formed from the intermediate oxidation state will then tend to decompose, to yield 2 or more different compounds, ones in which the element is present instead in these more stable oxidation states. 

 

A simple example is mercurous chloride, Hg2Cl2, which tends to decompose into a mixture of mercury metal, Hg, and mercuric chloride, HgCL2. Two atoms of Hg in the +1 oxidation state turn into one in the zero oxidation state (the element itself) and one with oxidation state +2. 

 I didn't really understand much of what they are getting at.  All I know about oxidation is that  it can cause rust - so I've been told.  But it did seem like an interesting piece for those who know all the forms and understand what happens with them.   Thank you for shedding some light on it.  I was hoping for such.

[exchemist]

 I didn't really understand much of what they are getting at.  All I know about oxidation is that  it can cause rust - so I've been told.  But it did seem like an interesting piece for those who know all the forms and understand what happens with them.   Thank you for shedding some light on it.  I was hoping for such.

Yeah, while I was writing the reply I was thinking that the concept of oxidation states is pretty hard to explain, simply, to someone who is not a chemist.

 

But  where there is hard science involved, my usual principle is to address it directly - and if anyone understands what I'm saying so much the better. :)  

[hazelm]

Yeah, while I was writing the reply I was thinking that the concept of oxidation states is pretty hard to explain, simply, to someone who is not a chemist.

 

But  where there is hard science involved, my usual principle is to address it directly - and if anyone understands what I'm saying so much the better. :)

How else would you challenge a reader to think?  :)

[GAHD]

It's like a new (process) to bond it so it doesn't become soluble as naked element, right? I guess they're saying they can combine it with some unexpected other more common material, make some salt that can go in a bucket.

[exchemist]

It's like a new (process) to bond it so it doesn't become soluble as naked element, right? I guess they're saying they can combine it with some unexpected other more common material, make some salt that can go in a bucket.

Possibly, though it looked me like more fundamental research into Pu chemistry, to understand what can go on in disposal sites for radioactive materials, for example.

 

I can imagine its chemistry may not be as well-researched as that of many elements, due to the difficulty of obtaining it and the precautions needed in its handling.