cb55555
Posts: 5
Joined: Wed Oct 15, 2014 1:50 am
Occupation: Amateur student

Please help with Expected (Redox?) Reactions for CLO2 & DMSO

Postby cb55555 » Wed Oct 15, 2014 4:17 am

I am keen to learn everything I can about the electrochemical properties and the likely reactions and products of the following molecules NaCLO2, CLO2 and DMSO in aquous solutions. First I would like to understand their likely reactions and products in-vitro, in the test tube, and then later, at some other time, perhaps, explore whether the same reactions and products could reasonably be expected to take place in-vivo, in mammals, and specifically in the human body.

I have been educating myself in the subjects of electrochemistry and redox reactions, but I seem to have gone as far as I can on my own, and would need help from here:

1.
My starting point is Sodium Chlorite (NaCLO2) mixed in the test tube with, say, 50% citric acid, or/and, as an alternative with, say, 10% hydrochloric acid.
I understand that in both instances there is going to be a REDOX reaction between the Chlorite and the acid and that one of the products of this reaction will be CLO2(g). I am not sure, however, about the exact nature of the clear liquid that is left behind by this reaction. Water, I suspect, is part of it, but what else? This liquid (at least when citric acid is being used) seems still quite sour and acidic, and I would like to know what it is, and whether it might be toxic, or still potentially useful for anything. The icing on the cake would be to see a balanced equation of the REDOX reaction by someone versant in this field and kind enough to answer my questions.

2.
After that first step, my primary interest would be the properties and likely behaviour of the chlorine dioxide (CLO2) gas, which I understand is typically generated in-situ to treat water and produce. The gas is quite irritating to airways and lungs when inhaled, and similarly "grates" (in stronger concentrations) on one's throat when dissolved in water. I would like to understand the details and nature of the bio- and electro-chemical reactions that are underlie these sensations, so any comments, including conjectures as to what might be happening there, would be appreciated.

3.
Beyond that, however, I would like to understand the electrochemical arrangements of the molecules and atoms when said CLO2 is dissolved in water. I have tried to figure out the exact nature of the molecular bonding on my own, but I am sometimes a slow learner and could not be sure if the CLO2 molecule, for instance, stays intact in solution (like water molecules remain intact relative to each other (dipolar bonding?)), or whether the component atoms separate temporarily (like the component atoms of NaCL are temporarily separated (ionic bonding?)) while dissolved in water. Any links or references to visual representations of the molecular bonding in this solution would be tremendously helpful. I would also welcome any comments or pointers as to the practical significance/implications to solutions having this or that kind of bonding between the various molecules. Maybe there cannot be dipolar bonding at all between different kinds of molecules, so please bear with me as I am trying to improve my grasp on these matters.

4.
I understand that CLO2 will slowly outgas from solution as CLO2, just like table salt and sugar will come out unaffected at a molecular level of their respective solutions. What would interest me here most is the CLO2 concentrations that may be achieved at low or no pressure, when, say, NaCLO2 is reacted with an acid in a reactor that is contained in a capped larger container, such as a screw-top jar, that itself contains water. Also, whether the volume of the gas absorbed will increase the overall volume of the water in which it is dissolved? And would all this be the same, or very similar, to the way CO2 is dissolved in water?

5.
And, if someone still has the patience and the interest, I would like to understand the solution one might get from CLO2 and (CH3)2SO (DMSO).
I have noticed this much, that CLO2 dissolves very nicely in a mixture of 70% DMSO solution (with 30% H2O), but have no idea as to the likely molecular structure and bonding that takes place between the three types of molecules in this complex solution, so the same questions seem to arise with regard to this solution as in 3 - 4 above. As a highly relevant aside, or indeed as a pre-requisite, I should try to get clear about the nature and molecular structure of the DMSO - water solution itself?

6.
And, finally, the very same questions as above concerning pure DMSO and CLO2. Will CLO2 dissolve at all in pure DMSO? And if so, will these have a stronger or weaker molecular bond as compared to CLO2 being dissolved in the above mixture of DMSO and water?

Grateful thanks in advance for any comments or pointers anyone would care to give me.

tdaly
Former Expert
Posts: 1415
Joined: Sat Nov 08, 2003 11:27 pm
Occupation: Planetary Scientist

Re: Please help with Expected (Redox?) Reactions for CLO2 &

Postby tdaly » Fri Oct 17, 2014 10:59 am

Hi cb55555,

What is the hypothesis you are trying to test? Parts of your post raise SERIOUS safety concerns. Sodium chlorite, hydrochloric acid, and DMSO are not chemicals you should be using without a fume hood, acid goggles, gloves, and a lab apron, at the very, very, very least. MSDSs for NaCLO2 and DMSO recommend a full face shield and respirator when working with these chemicals. DMSO penetrates many materials quite quickly, so glove selection is extremely important when working with DMSO. If you are doing this project for a science fair, you need to check with your science teacher and science fair administrators, if you have not done so already, before doing anything else.

Your comment about the taste of the liquid left by reacting NaClO2 with citric acid is worrisome - have you been tasting the product of this reaction? That is not a safe thing to do; you shouldn't do that with the products of any reaction you do in a lab. CLO2 gas is both toxic and explosive. Your comments about how the gas feels in your throat makes me think that you have been breathing the gas, which is extremely concerning. I can help you with some of the questions you have, but these are major safety concerns--red flags and alarm bells. These aren't chemicals to mess around with. If you have the proper personal protective equipment, are working in a lab under the supervision of someone who has experience with these chemicals, are doing this for a science fair project, and have the proper approvals from your teacher, I'm happy to help with your other questions. But before doing so I want to make sure that you are doing things safely and have the proper approvals in place.
All the best,
Terik

cb55555
Posts: 5
Joined: Wed Oct 15, 2014 1:50 am
Occupation: Amateur student

Re: Please help with Expected (Redox?) Reactions for CLO2 &

Postby cb55555 » Fri Oct 24, 2014 7:10 pm

Thanks,Terik. You are very kind.

Perhaps I should emphasise that my interests are theoretical. I want to understand the underlying chemistry behind treatment, disinfection and sterilization processes involving CLO2. I am a mature age, self-directed student, with life experience, and I am familiar enough with the overt physical properties and safety requirements of the substances involved. I would just like to understand the chemistry behind it all.

I understand that CLO2(g) is highly volatile and I sure wouldn't mess with it. It does, however, readily dissolve in water, where it is safe, and most useful. I have already done a lot of reading on its applications, but the literature does not appear to cover every aspect of its preparation, bonding state in solution, by-products, etc. Hence my questions.

Any help with these, but for the love of teaching and learning, would be appreciated.

tdaly
Former Expert
Posts: 1415
Joined: Sat Nov 08, 2003 11:27 pm
Occupation: Planetary Scientist

Re: Please help with Expected (Redox?) Reactions for CLO2 &

Postby tdaly » Sat Oct 25, 2014 12:20 pm

Hi cb55555,

I'm glad that these safety issues are taken care of! These particular forums are really for students, parents, and teachers working on science fair projects. So, your questions are better suited for a different online science forum. Best of luck in your endeavor!
All the best,
Terik

cb55555
Posts: 5
Joined: Wed Oct 15, 2014 1:50 am
Occupation: Amateur student

Re: Please help with Expected (Redox?) Reactions for CLO2 &

Postby cb55555 » Sun Oct 26, 2014 6:36 pm

Thanks, Terik. I am having difficulties identifying one. Would you care to suggest one for me?
Or, perhaps, I could send my email address to you to your BU listed email address?

Not sure what it is. In my field, we share knowledge and information with people for the sake of teaching and learning, but when I contacted an emeritus professor at one of the local universities here, he offered to answer my question as a consultant!!! There is no money in this for me, or anyone else, and I told him so. Still, he would not share, so go figure ...

cb55555
Posts: 5
Joined: Wed Oct 15, 2014 1:50 am
Occupation: Amateur student

Re: Please help with Expected (Redox?) Reactions for CLO2 &

Postby cb55555 » Wed Oct 29, 2014 4:07 pm

I guess, that means NO. ...

tdaly
Former Expert
Posts: 1415
Joined: Sat Nov 08, 2003 11:27 pm
Occupation: Planetary Scientist

Re: Please help with Expected (Redox?) Reactions for CLO2 &

Postby tdaly » Fri Oct 31, 2014 8:36 am

Hello cb5555,

I apologize for not seeing your post earlier. The policy is to keep all communication on the Ask an Expert forums, so email correspondence isn't an option, unfortunately. The policy exists for the safety of the students who use the forums. I haven't used other online forums, so I can't recommend any from personal experience. However, these two forums look like they would be a good fit for your questions:

https://www.physicsforums.com/
http://www.chemicalforums.com/
All the best,
Terik

cb55555
Posts: 5
Joined: Wed Oct 15, 2014 1:50 am
Occupation: Amateur student

Re: Please help with Expected (Redox?) Reactions for CLO2 &

Postby cb55555 » Thu Nov 06, 2014 4:12 am

Thanks, Terik. I will try them.


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