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How to Make Sodium Metal [HD Video Tutorial]

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video How to Make Sodium Metal [HD Video Tutorial]


First some safety: The experiment described uses corrosive chemicals and mixtures capable of burning without presence of atmosphere. It should be done outdoors in cotton clothing as fire protection, with chemically resistant gloves, and of course lab goggles. In case of fire, wait for initial reaction to subside, then use a class D extinguisher - do not attempt to put out fires with sand or water.

A recent experiment of mine involved the production of the highly reactive element sodium from sodium hydroxide and another less reactive metal, in this case magnesium. The reaction is as follows:

2Mg + 2NaOH = 2MgO + 2Na + H2

The magnesium (finely powdered) first ignites burning in atmospheric oxygen contained in the reaction vessel. This initial reaction produces enough energy to initiate the primary reaction. The Mg has enough desire for the oxygen contained in the NaOH to actually rip it from the hydroxide group, freeing hydrogen gas and sodium. The reaction is violently exothermic. More than enough energy is released to ignite the hydrogen gas which burns as the reaction progresses. The sodium is produced in a liquid state due to the temperature of reaction, and some of it vaporizes giving the flame a strong orange/yellow color.

To keep the sodium from burning immediately upon production, a loose fitting lid is placed over the reaction vessel, allowing the burning hydrogen to escape, but sealing the vessel off from atmosphere once completed. The lid is then not removed until the reaction cools to air temperature, at which point mineral oil should be added to the resulting slag to prevent further oxidation of the product.

Presumably this experiment could be preformed with other metals acting upon the hydroxide group, such as aluminum - in fact, I've heard aluminum gives a better yield because of a lower reaction rate and temperature which vaporizes much of the Na using Mg. I have not yet tried it. It is also quite likely that this process could free most if not all metals from their hydroxides because the reaction does not involve the metal contained in the hydroxide, but the hydroxide group alone. All hydroxides should therefore be susceptible to separation via magnesium and possibly aluminum. I will conduct further experimentation in warmer weather.
Workermark1 year ago
Can a brick be used instead of the heavy lid mentioned? Thanks
totally amazing!!!
NightHawkInLight (author)  solomonhorses2 years ago
Thanks!
taliran3 years ago
aaaaaamazing...
this is amazing please check out my instructables please thanks!!!!!!
leopard103 years ago
I probably couldn't do that but it is so COOL1
NightHawkInLight (author)  leopard103 years ago
Thanks! Please vote for it in the Epilog challenge!
Kaiven3 years ago
Still one of my favorite chemistry videos. I've been wanting to try this for a while now.
Gaark Kaiven3 years ago
I watch other people do these things so I don't have to ... :D
Rhamkota3 years ago
Do you mean wool? not cotton.
NightHawkInLight (author)  Rhamkota3 years ago
Wool does work nicely, but cotton also offers good fire protection and at a fraction of the cost.
true i am in sientific setion in high school and they told us that cotton is basily one of the ONLY thing that is good for all types of experiments.
love the video by the way!
corradini3 years ago
This is interesting but pretty incomplete. You casually mention "prepare graphite or carbon electrodes for electrolysis" as if that requires no add'l explanation for someone who's LOOKING for instruction, here - for something that makes chlorine gas and caustic lye(!) >;-) There's no discussion of the electrolysis -- it matters whether it's AC or DC, and what the voltage is.

Maybe I can help a wee bit: You're using, I believe, a Radio Shack (or similar, like the Coby CA-11 I've got sitting here) multi-voltage AC-> DC converter, so I'm guessing about 300mA max (esp. given that it took "a few hours"). No clues on the voltage switch position you've got it on, but you probably maxed it at 12, 'cuz why not? I'm also taking a WILD guess that your electrodes are pencil leads, hopefully from a #1 pencil (less clay/more graphite), which would probably be easiest to extract by the simple expedient of setting a pencil on fire.

My other (polite) gripe is that the comments under the video are essentially irrelevant - they're for (and from) another video of yours about the next step.

Finally: there're plenty of "don't try this at home or you will certainly die a horrible death" vids on Instructables (never mind YouTube ;-). This is one of them, and I think you need to be a little more forceful about that, particularly given that your instructions are pretty vague.

Let's review: we're igniting magnesium, which burns at 5,600F -- mixed with caustic lye which has roughly the same skin/eye-burning mojo as sulfuric acid. THEN we're pouring a flammable liquid into this mix which recently was burning at a few thousand degrees -- only now it contains elemental sodium, which we're tossing in water (in which it violently combusts and/or explodes), and said flammable liquid. OH - did I forget that we start out by generating chlorine gas, as in: a chemical warfare weapon banned since WWI? I probably left a few other blinding/maiming/choking/dying possibilities out, but that should do for the appetizer. (Oh, yeah - electrocution, if they use dad's battery charger or jumper cables or just strip zip wire and drop it in, which is absolutely a possibility given some of the idiot comments on some similar vids....)

Look: I love the overall process, and your intent - I don't mean to (pun intended) flame you. I just suggest, as a rather seriously experienced amateur chemist (and I do some very high-temp metalcasting as well) who still has all his fingers and binocular vision, that you add both some detail and some additional warning 'oomph'. 14-year-old trogloteens who can't spell the word "I" read this kind of stuff, and some will promptly run out and try it. Liability aside - you really probably don't want some dope kid to end up blinded and/or in the burn ward, or even burning his mom's trailer down...

Warnings Are Good. Detail is too. Best regards!
NightHawkInLight (author)  corradini3 years ago
What on earth are you talking about? This is NOT the electrolysis method of producing sodium that you seem to think it is. There is no electricity involved with this process, and no sodium chloride, therefore, no chlorine gas. I think you need to watch the video again and read the description. No more information is needed to complete this experiment than what is given.
(removed by author or community request)
Hey Ben,

Sorry - not sure whether you mean me or the OP (NightHawkInLight) is "dumb" and "doesn't know crud". Either way, though? Rude. Not nice. Not helpful. And untrue.

I goofed - my response was to both this post AND to his related post. (Seems he missed that, but that's another issue.)

However: he's obviously pretty smart, and does know rather a lot of stuff about chemistry, and this topic. I've got some quibbles, but they're pretty much about safety, not intelligence or accuracy. And - sorry - I own 2 chemical/energy companies, have 2 patents in the area of catalysis and reactor design filed and more coming, in conjunction with several PhDs in chemistry and chemical engineering.

So - whoever you're insulting -- me or the author -- bad move. Plus, it's against the site policy, and I've flagged your comment as such. Look - if you can't be nice, at least be CONSTRUCTIVE and rude... ;-)
You remind me of my friend Nick. lol he's got your sense of humor. I just deleted it so no hard feelings right? (And it was directed at the author)

BTW which companies?
NightHawkInLight (author)  corradini3 years ago
I have no other post that uses an electrolysis method. You must be confusing me with somebody else. What is shown in the video is all there is to this process, start to finish.
NightHawkInLight (author)  corradini3 years ago
Also, at no point do I say, "prepare graphite or carbon electrodes for electrolysis" as you have presumed to have quoted me, because again, this is NOT an electrolysis experiment and no electrodes are needed. I have no idea where you pulled that quote from.
crjeea3 years ago
Still think carefully removing the Lithium from Lithium batteries is quicker.
you must loose quite a bit of Sodium along the way in this reaction and it doesn't appear to be that pure at the end but still not much effort and a fairly fiery reaction so looks good enough. may well give it a go next time I get hold of some Magnesium.
Minifig6663 years ago
Awesome!
I guess the same wouldn't work using potassium hydroxide?
Would a proper fuse be necessary or could I just use some newspaper?
Also how dangerous do you think it would be to melt it under mineral oil to turn it into a proper ingot?
Thanks!
-Minifig666
NightHawkInLight (author)  Minifig6663 years ago
It actually would. This experiment should work with any metal hydroxide because the metal has nothing to do with how this reaction progresses.

You will need a real fuse, or an electrical igniter. An electrical igniter could be as simple as a model rocket igniter from a hobby store, or a christmas light bulb igniter which I show how to make here: http://www.youtube.com/watch?v=cXXIfLTSP-c

Melting sodium or potassium under mineral oil is as dangerous as it sounds. You would have a flammable liquid hotter than the boiling point of water that would be very dangerous should it spill, and a reactive metal made more reactive because of increased temperature. If you intend to try it I highly suggest that your melting pot is clamped in a vice while heating so that it cannot be spilled. Keep a lid nearby to extinguish the flame should it catch fire. Obviously water extinguishing oil or a reactive metal is not an option.
Ok thanks, I feel a big purple flame coming along shortly!
If I ever get a vacuum pump that works I could have a go melting it 'in vacuo' or perhaps under argon! For now I'll have to dig out my extinguisher and give it a go, it shouldn't take too long to bring potassium up to 63oC with a torch... :)
I'll get back to you on how well the melting goes...
-Minifig666