[pzona69]

When dissolving an aqueous solution of an ionic compound, sodium chloride for example, is there a way to keep the Na⁺ separate from the Cl^- ions, as in to yield sodium and chlorine, rather than salt? Obviously I don't want to do this because of the dangers of chlorine gas, I just used that as an example.

I figure electrolysis would end up yielding sodium chlorate (or perchlorate?) and hydrogen gas, but maybe I'm wrong.

I was just wondering for no particular reason I guess.

[Mitch]

No there isn't. But the electrolysis of molten NaCl will achieve what your looking for.

[pzona69]

What is, or how do I figure, the melting point of NaCl? I never learned to do it for binary or polyatomic compounds. Also, you mean the actual molten NaCl, not a solution of it, correct?

[Arkcon]

The melting point of NaCl is approx. 800 C.  Most ionic salts melt at very high temperatures, given the strength of the ionic bond.  I once wanted to play with electrolysis of NaCl, but 2 propane blowtorches going under a crucible of NaCl could only barely sinter it.  Which is just as well, I wasn't really ready for all the things that could go wrong ...

[Rabn]

I had a thought...literally a thought, never attempted any calculations...that it may be possible to obtain solid sodium by the following procedure:

-pour a lot of NaCl into a beaker, like maybe 200g
-pour mineral oil over the sodium until there is about 3 inches of oil over the top of the salt.
-place a negative electrode into the undissolved salt and the positive electrode into the solution about 1 inch below the surface of the oil.
The electrodes would be hooked up to a DC source that allows for a very high voltage. The thought is that the sodium would crystallize around the negative electrode and chlorine gas would form on the positive electrode. Using mineral oil because of its low flammability and its ability to store sodium without rapid oxidation and the resultant fire/hydrogen gas.

like I said I really haven't thought this through so I'm sure it most likely won't work but it may give someone something to work on....

[Arkcon]

Interesting ... does mineral oil really conduct electricity that well?  I'd heard that mixing NaCl with KCl will lower the melting point enough for it to be easily melted.  But then you get an alloy of sodium and potassium.  As if it is ever a good idea for a layman to have either of those metals.  There is always the Castner-Kellner process, wikipedia has a nice diagram.

[billnotgatez]

http://www.corrosion-doctors.org/Electrowinning/Sodium.htm

Downs Cell

FYI

[Borek]

Interesting ... does mineral oil really conduct electricity that well?

As far as I know - it doesn't. Neither solid NaCl does. It won't work.