Anodes and Cathodes

[Rob]

What should i use for the anode and cathode in the electrolysis of NaCl - two Carbon or something else?

Regards

[gonelli]

Uhhh... I don't think you will be able to perform the electrolysis of NaCl.

 

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This just occurred to me, are you referring to the electrolysis of water in a NaCl solution? Where you will end up getting H[math]_{2}[/math] and O[math]_{2}[/math]?

Edited March 18, 2009 by gonelli
Merge two posts

[Theophrastus]

Expanding upon what gonelli said, if you are doing an electrolysis of NaCl, you are to be forewarned that the melting point of NaCl is 1074 degrees Kelvin (800 degrees celsius/centigrate). The heat required, is what makes this process difficult to enact. If you were refering to the electrolysis of water, adding salt, to increase its electrical conductivity, certainly, various metals, could be used. Personally, I like to use copper and magnesium, however, I know that many like to use graphite. Some also use nickel or platinum, due to their catalytic properties, accelerating the reaction. To properly answer this question, I must ask, are you doing an electrolysis of NaCl, or H2O, and what do you desire to achieve or produce, from this reaction?

[Rob]

mmm, i could have been more specific. I mean aqeous NaCl, with a view to obtain Sodium Hydroxide, Chlorine and Hydrogen.

[hermanntrude]

Expanding upon what gonelli said, if you are doing an electrolysis of NaCl, you are to be forewarned that the melting point of NaCl is 1074 degrees Kelvin (800 degrees celsius/centigrate).

 

Bad theophrastus! Bad!

[UC]

mmm, i could have been more specific. I mean aqeous NaCl, with a view to obtain Sodium Hydroxide, Chlorine and Hydrogen.

 

Do a google search for chlorate cells and read about the electrode choices (especially the anode, which is under much harsher conditions) for them. These are the rugged kind of electrodes you want.

[Theophrastus]

To Rob: Ah, now I see. Theoretically speaking, it should work, however, I've tried the experiment myself, and found the yield, to be most unsatisfying. However, I did perform the reaction over a span of two days, and i suppose, were one to let it ensue longer, the numbers may add up. I was thinking that one could theoretically increase the yield, by using a catalyst, adding heat, (something along those lines) etc. However, perhaps, you may outdue me, as I do not pretend to be an expert. And I agree with UC in looking up the electrodes based on your needs and setup, on google. (Ah google, the ultimatum of search engines) Cheers! Best of luck in your experimentation!

 

To Hermanntrude: I sense I did something wrong, but what? If it was the degrees Kelvin, is there perhaps a problem with using that system of measurement, or is it that the number I gave, was off by one. Looking back, I believe it is so... or... what?

[insane_alien]

kelvin is not done by degrees.

[hermanntrude]

i was only being silly, by the way. it's all tongue-in-cheek.

[salter]

If you do electrolysis of NaCl in solution it is going to be hard to find something that doesn't react... if you want [ce]H2[/ce] and [ce]O2[/ce] do yourself a favor and use NaOH. I've tried pretty much everything save platinum and carbon... i've heard carbon works.

 

And to theo: your problem is the current. You need to use a car battery... i was able to get 34 cc of hydrogen in 15 minutes.

 

If you use copper you will get copper (II) chlorides like [ce]CuCl4^2^-[/ce] as well as NaOH and [ce]H2[/ce]... As for the Cl your gonna need something tough.

[hermanntrude]

please be extremely cautious with these experiments. They can often give unexpected results and there is often the danger of creating chlorine which can very badly damage lungs. Also if you use a car battery, be aware they can give nasty shocks and contain some vicious chemicals. Also be careful with the hydrogen if you make any. On its own it's dangerous enough but if it mixes with air or oxygen or chlorine etc etc it can be extremely explosive