[pzona69]

This is just something I tried to do the other day, for no particular reason. I took about a tablespoonful of table salt (non iodized) and tried to oxidize it with H₂O₂, but nothing apparently happened, it just got wet.

I'm not sure if there was some type of additive that might prevent the reaction of the hydrogen peroxide with the sodium chloride. Is there some type of condition that needs to exist for this reaction to take place, or something like that?

I asked about the oxidation of KI on this forum before (thanks for the *delete me*), and I figured NaCl would behave similarly (2NaCl + H₂O₂ -> 2NaOH + Cl₂??). I considered the difference is that the chlorine molecule is a gas and the iodine in the KI oxidation reaction is a solid, but I don't know why this would make a difference.

I was just curious as to why two apparently similar alkali metal-halogen compounds would behave so differently like this.

[Arkcon]

Na and K are similar enough, so that's a fair guess on your part there.  But Cl is much more electronegative than I, therefore, you'll need something stronger than household H2O2.  Even without looking at a table of electronegativities, the periodic table gave you a hint -- there's another element, Br, between Cl and I

[pzona69]

What type of oxidizing agent would I need then? I was going to try to make soap at some point, just for fun, and since you can't really buy NaOH in stores anymore (it's used in drug manufacture, apparently), I wanted to try to make my own. I realize it's still fairly easy to get, but half the fun for me is making all my own ingredients.

[Borek]

If something is already oxidized it can't be oxidized more. That's not necesarilly full truth about the situation, but you may accept it as a starting point

To produce NaOH from salt you may try electrolysis of NaCl solution. But that's rather dangerous -  evolving chlorine is a poison and if mixed with hydrogen evolving on the cathode it can explode.

[pzona69]

Did you mean that the reaction using NaCl to produce NaOH would not be an oxidation?  I'm trying to think of other ways of doing this without using a simple substitution with another metal hydroxide.  I figured that electrolysis, like you said, would be dangerous because of the chlorine.

Maybe I could use some type of alcohol? I'm by no means experienced in organic chemistry (I'm only about to start my second semester of high school organic chem), but I figure if I react the NaCl with ethyl alcohol, I get chloroethane and NaOH. Would this be correct?

[IITian]

I guess electrolysis is your best bet to get NaOH out of NaCl. If you use concentrated solution of NaCl, be careful not to inhale the gases generated during the process. Very dilute aqueous solutions of NaCl won't be of much use in this case.

[Arkcon]

Did you mean that the reaction using NaCl to produce NaOH would not be an oxidation? 

Yes, you see it is already oxidized as NaCl, the reduced form would be free sodium metal and free chlorine gas.  You could then oxidize the sodium metal again, using water, instead of chlorine, to make NaOH.  Not that free Na is easy to get, or easy to handle.

Maybe I could use some type of alcohol? I'm by no means experienced in organic chemistry (I'm only about to start my second semester of high school organic chem), but I figure if I react the NaCl with ethyl alcohol, I get chloroethane and NaOH. Would this be correct?

You are free to experiment to determine the result.  I don't want to discourage you.  But in the original post and in this post here, you are simply combining words and letters that make up chemical names to come up with your conclusions, and chemistry works under different rules.  Pay attention in class, you'll get there.

[Kryolith]

It is possible to oxidize the chloride ion in NaCl to chlorine using KMnO₄ in acidic solution.
NaCl doesn't react with ethanol, a small quantity will just dissolve. However chloroethane reacts with NaOH to ethanol and NaCl.

[pzona69]

Yeah I tried reacting them, I think the small amount of NaCl that did dissolve just lowered the boiling point a little bit. I didn't do the work to figure the change, but the alcohol came to a boil in about a minute, which is quicker than usual.

You are free to experiment to determine the result.  I don't want to discourage you.  But in the original post and in this post here, you are simply combining words and letters that make up chemical names to come up with your conclusions, and chemistry works under different rules.  Pay attention in class, you'll get there.

Once I thought about it, you're right, NaCl is ionic with a substantial electronegativity difference; it was kind of dumb to think it would react with an organic compound like that.  I do realize I'm not very experienced with this kind of thing. In school we didn't study so much what reactions will and won't work, but more balancing reactions and finding a missing product or reactant. What I know about actually reacting things, I had to learn myself from one place or another.

Do you have any suggestions or resources for creating NaOH? Being that I'm in high school I'm kind of limited in what chemicals I can obtain, so I'm using mostly household items and whatever I can find in a drugstore.

[Kryolith]

Yeah I tried reacting them, I think the small amount of NaCl that did dissolve just lowered the boiling point a little bit. I didn't do the work to figure the change, but the alcohol came to a boil in about a minute, which is quicker than usual.

The boiling point should increase.  Further information:

http://en.wikipedia.org/wiki/Colligative

[pzona69]

That's what I meant when I said I didn't work it out. I didn't measure the NaCl very precisely (I used about 4 spatula scoops), so I couldn't find the molality. I only meant that it seemed like the boiling point dropped, but it was probably because I heated it on high (I use a hotplate rather than a flame burner) right away instead of gradually increasing the temperature.

[Kryolith]

I use a hotplate rather than a flame burner

That's very clever. Ethanol is inflammable, so a flame burner should never be used. The phenomenon of boiling point elevation also occurs, when you put salt into a cooking pot with boiling water. Moreover it takes longer to boil salt water.

[Arkcon]

Do you have any suggestions or resources for creating NaOH? Being that I'm in high school I'm kind of limited in what chemicals I can obtain, so I'm using mostly household items and whatever I can find in a drugstore.

If you give your high school teacher a good enough reason, they may give you a few grams.  If they can spare it.  And if you've shown that you can work carefully enough.  And if you're a good enough student.

If you're making a batch of soap, search on this board.  Another person is trying to put the Ivory Snow people out of business, and may have a hobbyists source of hydroxide for you.

[Mr. Jack]

EtOH is flammable in concentrations higher than ~60%.  If you are wanting to make NaOH, electrolysis of NaCl water is not exceptable unless you seperate the 2 anodes with some kind of ion exchange material (asbestos?).  If you don't do that you will basically get bleach because of the chlorine dissolving in the water to create HClO and HCl and then that reacting with the NaOH creating NaHClO and NaCl (bleach).

I would say the best way is the controlled (as much as you can) reaction of metallic Na with water.  Unfortunately Na is incredibly expensive and difficult to obtain (probably because of the methheads using it for birch reductions.)

Speaking of sodium.  Check this out.

http://www.youtube.com/watch?v=HY7mTCMvpEM

What an atrocity!

[Borek]

EtOH is flammable in concentrations higher than ~60%

From my own experience it is possible to burn 40% vodka if you know how to ignite it. Done that personally. Trick is to use two matches.