Sciencemadness Discussion Board

An interesting oxo-cation of chlorine: chloryl, ClO2(+)

woelen - 5-3-2020 at 12:31

In one of my books I read about chlorine, being capable of forming a cationic species ClO2(+) and that this ion even can form solid salts. Two examples of such salts are ClO2SbF6 (chloryl hexafluoroantimonate) and ClO2ClO4 (chloryl perchlorate). These salts are red, due to the red color of the chloryl cation.

I decided to try whether I can make this ion, not in a solid salt, but in solution. Making this requires quite extreme reagents, but SO3 is capable of doing it. When you add potassium chlorate to oleum, then the SO3 strips off one oxygen ion from the chlorate anion, and a chloryl cation remains. So, this is not a redox reaction, the chlorine remains in oxidation state +5.

The solution has a lovely bright red color. I made a webpage about this, with pictures. It is really nice to see the color of this cation ClO2(+) and to be able to do some little experiments with it. I did not do many experiments with it, I only made a tiny amount of it. It is dangerous stuff and hence I did not want to make more than a few tens of mg of this in total.

https://woelen.homescience.net/science/chem/exps/chloryl/ind...


[Edited on 5-3-20 by woelen]

DraconicAcid - 5-3-2020 at 12:49

Very cool!

Syn the Sizer - 5-3-2020 at 13:40

Quote: Originally posted by woelen  


https://woelen.homescience.net/science/chem/exps/chloryl/ind...



I checked out your experiments on the page, I love the reaction with nitric acid, iron fillings and gimp, I have no shortage of gimp and at some point I am going to try using it to colour other gasses, or maybe even solids.

The best part is gimp is available to everybody, no restrictions.

Sorry I realize this is a digression from the original topic, but I had to mention it.

[Edited on 5-3-2020 by Syn the Sizer]

njl - 5-3-2020 at 14:48

@Syn could you link that page? I can't find it

Syn the Sizer - 5-3-2020 at 16:03

Quote: Originally posted by njl  
@Syn could you link that page? I can't find it


https://woelen.homescience.net/science/chem/exps/Fe+HNO3+Gim...

Yah, I don't know why I quoted the original post instead of linking the one I was talking about, my bad.

[Edited on 6-3-2020 by Syn the Sizer]

DraconicAcid - 5-3-2020 at 16:49

Quote: Originally posted by Syn the Sizer  
Quote: Originally posted by woelen  


https://woelen.homescience.net/science/chem/exps/chloryl/ind...



I checked out your experiments on the page, I love the reaction with nitric acid, iron fillings and gimp, I have no shortage of gimp and at some point I am going to try using it to colour other gasses, or maybe even solids.

The best part is gimp is available to everybody, no restrictions.


What the frick is gimp?

Syn the Sizer - 5-3-2020 at 18:24

Quote: Originally posted by DraconicAcid  

What the frick is gimp?


I am sure it was meant as a joke by Woelen, Gimp stand for "GNU Image Manipulation Program". Essentially opensource Photoshop, the images were manipulated so the brown showed red or blue. I was just running with the joke and, since its opensource its available on OSX, Windows and Linux so it's "available to everybody" and there are "no restrictions" lol.

Sorry I have an odd sense of humour.



[Edited on 6-3-2020 by Syn the Sizer]

SWIM - 5-3-2020 at 18:46



I thought they meant this guy.

https://www.youtube.com/watch?v=S8kPqAV_74M

Puts a whole new spin on "Available to everybody, no restrictions."



[Edited on 6-3-2020 by SWIM]

Syn the Sizer - 5-3-2020 at 19:47

Lol, that's for sure

DraconicAcid - 5-3-2020 at 22:14

Quote: Originally posted by Syn the Sizer  
Quote: Originally posted by DraconicAcid  

What the frick is gimp?


I am sure it was meant as a joke by Woelen, Gimp stand for "GNU Image Manipulation Program". Essentially opensource Photoshop, the images were manipulated so the brown showed red or blue. I was just running with the joke and, since its opensource its available on OSX, Windows and Linux so it's "available to everybody" and there are "no restrictions" lol.

Sorry I have an odd sense of humour.



[Edited on 6-3-2020 by Syn the Sizer]


AH, got it.

Bedlasky - 6-3-2020 at 11:11

Great experiment!

I some time ago read about chloryl perchlorate and other mixed chlorine oxides (ClOClO3 and ClOClO2). They are really interesting compounds. ClO2ClO4 can be make by oxidation of ClO2 with ozone. Other two oxides can be make by photolysis of ClO2 under UV light, first at room temperature, second at temperatures below 0°C. They decompose in to chloryl perchlorate, chlorine and oxygen.

Thanks for showing this interesting chlorine chemistry.

chornedsnorkack - 8-3-2020 at 00:47

So, when you slowly add concentrated sulphuric acid to oleum, and cool to reduce temperature, when does the orange slowly start to turn yellow and give off chlorine dioxide?
Also, how does the heat of dilution of sulphuric acid or oleum compare with heat of melting of ice? Does a piece of ice in oleum give off heat?

woelen - 8-3-2020 at 03:46

I expect that you need to add quite some ordinary H2SO4 to the orange solution before the ClO2(+) ion is destroyed. As long as there is free SO3, no HClO3 will be present and hence no ClO2 is formed.

The heat, produced on diluting oleum with water is not comparable with the heat, produced on diluting 96% H2SO4. If you add oleum to water, then you get an explosively violent reaction. Even the reaction of sodium with water is tame, compared to the reaction between oleum and water. You must have seen that reaction yourself, it really is scary. I expect, that if you add a chunk of ice to oleum, that this will result in an explosion. E.g. if you throw a piece of ice, the size of a bean, in a test tube in which there is a few ml of oleum (having a few tens of percent of free SO3), then I expect a loud crackling noise or a hefty PANG and ejection of a lot of liquid from the test tube. I have never tried though. Maybe an idea for another video :D

chornedsnorkack - 8-3-2020 at 06:18

Quote: Originally posted by woelen  

The heat, produced on diluting oleum with water is not comparable with the heat, produced on diluting 96% H2SO4. If you add oleum to water, then you get an explosively violent reaction. Even the reaction of sodium with water is tame, compared to the reaction between oleum and water. You must have seen that reaction yourself, it really is scary. I expect, that if you add a chunk of ice to oleum, that this will result in an explosion. E.g. if you throw a piece of ice, the size of a bean, in a test tube in which there is a few ml of oleum (having a few tens of percent of free SO3), then I expect a loud crackling noise or a hefty PANG and ejection of a lot of liquid from the test tube. I have never tried though. Maybe an idea for another video :D

Remember that ice has a big latent heat of melting:

The Acid in Water Puzzle
www.chem.indiana.edu › wp-content › uploads › 2017/11
In sulphuric acid, ice actually cools.
Soft snow might be a good place to throw oleum into. The porosity and compressibility of snow means that if oleum does explode, it would only explode at the bottom of snow, make a hole in the bottom of snow by compressing snow out of the hole, not disturb the top of the snow and close the small hole through which it fell into snow when the compression of explosion squeezes the bottom of the hole shut.

But oleum, unlike sodium, might not explode with snow at all.

unionised - 8-3-2020 at 08:00

GIMP notwithstanding, I'm amused by the idea of reacting a blue gas- ozone, with a yellow/ green gas- ClO2 and getting a red liquid- chloryl perchlorate.

woelen - 8-3-2020 at 11:36

That reaction is not for the faint of heart :P Both reactants and the product are not the most stable compounds! But indeed, it would be very cool to watch that reaction.

@chornedsnorkack: I am afraid we will never know. I will not use my very hard to obtain and expensive oleum for pouring it down in some snow.