hermanntrude

No, you CAN'T make sodium!

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We frequently get amateur chemists posting here thinking they have found a way to make themselves some sodium, which they see as incredibly exciting because it reacts with water.

Most of these methods involve electrolysis. Let me explain, once and for all why this idea is wrong and foolish:

1) The reduction potential of sodium is very negative. This means that it likes to be Na+ and doesn't like to be Na at all. However, water has a much smaller reduction potential, and will easily be reduced to give hydrogen gas and hydroxide ions. The difference between the reduction potentials is so enormous that you will NEVER make sodium by reducing a sodium salt in water. You do however have a chance of making some chlorine at the other end if you decide to use sodium chloride. If you do this, you'll be making a very toxic gas which will burn your lungs in nasty ways. Be careful!

A side-point to aqueous electrolysis should be bloody obvious to people but it isn't. That is, that if you DID somehow miraculously manage to reduce sodium onto your cathode (perhaps you're Jesus), then it would immediately react with the water to make sodium hydroxide again, spitting and flames inclusive.

2) There is another method for making sodium and at least this one is actually possible. It is the electrolysis of molten sodium chloride. The trouble here is that while this is fairly easy to do on an industrial scale in specially built vessels, it's very difficult to do on a smaller scale, not to mention extremely dangerous. Molten sodium chloride is not pleasant, and it's very difficult to get to those kinds of temperatures. Sodium hydroxide was another suggestion I read on the forums, and while it certainly has a lower melting point, we're talking about a strong base here... do you REALLY want a molten puddle of fuming, spitting sodium hydroxide in front of you? REALLY? No. You don't.

3) Just because you can write and balance an equation it doesn't mean it will happen. The reasons behind what reactions will "go" and what reactions won't are quite detailed and beyond the scope of this thread. However, in general, things which are considered unstable (like sodium) are difficult to make (they require less stable things in the first place, or giant amounts of energy). So, NO, you can't make sodium by doing a simple displacement reaction or a precipitation reaction.

So all-in-all the net result of the above is NO! You CAN'T make sodium!

The above also applies to the other alkali metals

Edited by imatfaal
removal of chem tags that don't work now
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Ditto for Magnesium, which keeps turning up as well, unless of course, you have sodium to waste.

Edited by UC

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Excellent choice, in stickying this point. Everyone I know, when they first start chemistry, have a taste for things that "go boom." Metallic sodium is one of many of the compounds that go upon this list. The other alkali metals, acetylene gas, and homemade 90% hydrogen peroxide are among other sought after compounds, that are not as easy to make, but seem to be much desired. It's interesting, that everyone seems to have a natural affinity to using electrolysis as their "magic bullet," as you fairly pointed out. Certainly a worthy topic for the psychology thread. :)

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The above also applies to the other alkali metals

 

Ohh, ohh, I think I electrolysed myself some cesium!

 

Hermann is way ahead of you :P

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You can always buy it off of unitednuclear.com XD

 

Would it work to put some metal like Mg in NaOH solution? Granted, if it did work it would react with the water but I'm just curious.

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You can always buy it off of unitednuclear.com XD

 

Would it work to put some metal like Mg in NaOH solution? Granted, if it did work it would react with the water but I'm just curious.

 

No. Please learn what this means and how to use it: http://openlearn.open.ac.uk/file.php/3258/T357_1_ie001i.jpg

 

"Galvanic series" or "electromotive series" are helpful things you might punch into google, which I will not do for you.

 

Granted, everything is an equilibrium, so transiently and randomly, some magnesium might make a few sodium ions into sodium metal, but they will immediately give up those electrons to water or back to the magnesium ions that were formed.

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The people who post in this thread are reminded that there is a serious "Hazardous Material" rule in SFN rule book. Posting instructions that can result in people potentially getting hurt or hurting others is not allowed in this forum.

 

Please be advised that sodium is a hazardous material prone to violent reactions and any preparation of it is inherently dangerous. No preparation method is without severe hazards that range from property damage to blindness, and possibly death in the most extreme of circumstances.

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No? :eyebrow:

 

pretty lousy synthesis if you can't purify the sodium... anyway, what proof do you have that you/they made sodium? it reacts with water? so would hot powdered magnesium... so would a lot of things.

 

I'm not saying you/they didn't make sodium... i'm saying you/they haven't proven it, and the burden of proof is on you or them.

 

I also have concerns about your reaction vessel... what was the pan made of? how can you be sure it wasn't involved in the reaction?

Edited by hermanntrude

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I'd actually go out on a limb and say there probably is some sodium in there. That reaction with water is quite too violent for magnesium, I would think. Magnesium is, however, not a stronger reducing agent than sodium at high temperatures. Sodium, however, is volatile and will boil off from the reaction site if enough heat is supplied. Reactivity series can be cheated by Le Chatlier's principle. This heat is probably being provided by the reaction of the hydroxide portion of NaOH with the Mg, forming Na2O, MgO, and H2.

 

The flames gushing out of the pot are probably burning hydrogen and some sodium vapor. That pot looks to be aluminum, which is a horrible choice, since it reacts with sodium hydroxide.

 

While impressive, the amount of sodium formed is probably very small and and it is finely divided, trapped in the debris. The reaction with water was far too fast for any significant amount of Na to be present.

 

Splashing paraffin in is a horrible idea. Anyone who has ever worked with concentrated NaOH knows that it's nasty and molten NaOH, which you could expect to find in the reaction mix will instantly blind you if it gets in your eye and cause some pretty horrible wounds if it gets on your skin. The paraffin is also flammable, which introduces further hazards. A stream of chilled argon would be far superior, but if you can get that, you probably wouldn't be needing to make sodium, especially like this.

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NO?? WE CANT???

It seems it is a sad factor for mee...Coz i like BOOOOMS and ya know Na is very expensive in Sri Lanka.... Ohhhh

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Oh, it gets even better. In his response to his first video, he actually isolates the sodium.

 

Link Removed by Moderator due to safety concerns

 

No need to rant about the part at 1:38- we all know it was pretty stupid; aside from that, he was able to extract considerable amounts of sodium metal, which makes the process feasible and places sodium production within the realm of possibility for a citizen chemist.

 

By the way, the pot is most likely stainless steel, making it inert from the reaction.

Edited by Mokele

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that synthesis seems to have worked but as you can see it's extremely dangerous. Anyone reading this thread should think LONG and HARD before attempting to recreate the reaction. Note that the guy who did the reaction was badly hurt and could easily have been blinded or permanently scarred.

 

Even without the extremely silly idea of pouring water onto hot sodium, the rest of the reaction could use a bit more attention to safety.

 

To be honest i'm not totally comfortable with this link being on our site for the safety of some of our more confident and less-skilled members.

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I understand that we have to be careful in this type of thread because everything we say is open for the public, and for stupid kids to try and blow themselves up, so I cannot go into any details, but I will say this: It is possible to synthesize moderately pure sodium using no electricity, and using only washing soda, pickling lime, magnesium pencil sharpeners, and rudimentary tools commonly found in the kitchen and the garage. It's not safe without proper safety equipment, but I'm just saying, it's not impossible to synthesize sodium in you're backyard if you know what to do.

 

By the way, sodium bought from sites like United Nuclear is outrageously overpriced because of its dangers, so yeah, I'll just make my own. You can really tell that it's overpriced because it's way more expensive than lithium LOL.

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OK. I've done some experiments and have determined that the chemical equation for synthesizing sodium by reducing from its hydroxide using magnesium is:

 

2Mg + 2NaOH --> 2MgO + 2Na + H2

 

This reaction is very interesting, because a more electropositive element is being reduced by a LESS electropositive element. It happens because the magnesium is reducing both the sodium and the hydrogen in sodium hydroxide, making it exothermic. It is also dependent on the fact that the lattice energy of sodium oxide is less than that of magnesium oxide. This is because sodium ions have a smaller charge than magnesium ions, decreasing the lattice energy and making this reaction possible. If sodium oxide were more stable, the reduction would stop after hydrogen. If you still don't understand this reaction, let's break it up to better represent what is going on.

 

Mg + 2NaOH --> MgO + Na2O

Mg + Na2O --> MgO + 2Na

 

These 2 equations add to get the total equation shown above.

 

If you're wondering what my source is, I looked enthalpies of all these compounds and puzzled with the possibilities on paper, and determined that equation, and then verified it by making half a gram of sodium using this method. All the predicted products were created. The hydrogen burns yellow as it comes off because of sodium ions present in it. The reaction was so hot that it heated my brand new crucible to nearly 1,100 degrees celcius (orange-yellow color) and cracked it in half. Better get a new crucible.

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The people who post in this thread are reminded that there is a serious "Hazardous Material" rule in SFN rule book. Posting instructions that can result in people potentially getting hurt or hurting others is not allowed in this forum.

 

Please be advised that sodium is a hazardous material prone to violent reactions and any preparation of it is inherently dangerous. No preparation method is without severe hazards that range from property damage to blindness, and possibly death in the most extreme of circumstances.

 

Yeah, I'm thinking we all need to do a get together and discuss that SFN rule/issue some more. To continue that process will make SFN an amature science forum, which suggests that people take their scientific abilities elsewhere. If you feel it's necessary to delete this post, then do so. I consider conducting gene therapy much more hazardous than trying to obtain sodium.

 

For what I remember, getting sodium is generally an industrial process. Sciencemadness seems to go into detail with a couple of threads. In general, however, I believe a person needs a "Downs cell" in order to split salt and generate atomic sodium. The process is dangerous, primarily because chlorine gas is created, which can kill you (it was used in world wars) and then there is the exothermic property of sodium which can kill a person, which is another incredible danger. And the temperatures required to do the process are also dangerous, which makes the process of obtaining sodium from a Downs cell more than dangerous; and it should not be conducted unless the person has knowledge in chemistry and industrial safety practices. In general, there is a large danger involved with this process.

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genecks, you are correct, the process is very dangerous, and yes a down's cell is the normal method on the industrial scale.

 

We have no objection to discussion of the way it is done, what we don't like is people who think they can do it by a method they invented themselves using a 9V battery and some salt from the kitchen. people like that are not scientists and can cause themselves and others serious harm.

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Well it looks like this thread hasen't had a post in a while but this topic realy dose interest me, If I were to do this which I woulden't because im an amature and I dont want molten sodium on my face but anyways; What is the point of making mettalic sodium when sodium in compounds is so much more usefull? How is it made in the industry and why would anyone buy mettalic sodium for anything else than throwing it in water and watching it go boom, if you want to do that get an acid and replace the hydrogen with a reactive metal and light a match, you will probably get acid all over you. With so many other "safe" explosives that are more spectacular than sodium why make it or even use it?:confused:

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Sodium metal is very useful for making sodium amide, which can then be used to make azides. Lead azide is one of the most practical primary explosives. Also, the reason people love throwing sodium metal into water so much is because it's fascinating that something will actually react with water, which is normally considered somewhat inert, so vigorously that it explodes. =) When I thew a bunch of sodium beads into water on my driveway, i got lots of cheers from my audience lol.

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Try melting NaC sodium carbonate and try performing electrolysis my brain says it will seperate into carbo and sodium metal

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If you think sodium carbonate is NaC... I wouldnt even let you have a go cooking for me :doh: It is Na2CO3

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Could you not electrolysise molten sodium chloride? i know it would be a hugely high temperature, but could you not theoretically do it?

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