Sciencemadness Discussion Board

Sodium and Potassium Usefulness.

TheNerdyFarmer - 23-11-2016 at 19:39

I was watching a couple videos on youtube about sodium and potassium and started thinking about how cool it would be to have sodium. But then got to thinking, what good uses (if any) would sodium or potassium metal have in a lab other than some good fun every now and then? It seems like they are pretty useless in making anything more than their hydroxides.
If anyone knows of any valuable uses please do say.

Metacelsus - 23-11-2016 at 20:02

They are good reducing agents, and can also make things like alkoxides.

[Edited on 11-24-2016 by Metacelsus]

j_sum1 - 23-11-2016 at 20:29

Here ya go.
https://www.youtube.com/watch?v=umYuJ8TwQLk

A bit unorthodox (ok a lot) but it does show that this is more than just a curiosity.

Na is often used as a drying agent. Sodium ethoxide is a fairly common starting point for many processes -- formed from the reaction between sodium and ethanol.

careysub - 23-11-2016 at 21:32

Take a look at these key reactions:
http://www.masterorganicchemistry.com/2011/10/07/reagent-fri...

And these reports on various reagents prepared from metallic sodium:




Attachment: SodiumAmalgam.pdf (76kB)
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Attachment: SodiumEthoxide.pdf (87kB)
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Attachment: SodiumMethoxide.pdf (252kB)
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DrP - 24-11-2016 at 02:27

We used to make sodium wire out of it to keep distilled solvent dry.

Others in our group were using both of those metals as a catalyst for certain polymerizations.

Meltonium - 24-11-2016 at 06:53

You could also use sodium metal to make sodium hydride, a useful chemical in organic synthesis, or even sodium borohydride.

ecos - 24-11-2016 at 07:27

you can make H2O2 from Na.

Jstuyfzand - 24-11-2016 at 07:30

Quote: Originally posted by ecos  
you can make H2O2 from Na.


Could you elaborate?

Maroboduus - 24-11-2016 at 08:28

And nobody mentioned sodium amide yet.

And how could anybody make buna rubber without it? (or should it be BuNa?)

Metacelsus - 24-11-2016 at 09:25

Quote: Originally posted by Jstuyfzand  
Quote: Originally posted by ecos  
you can make H2O2 from Na.


Could you elaborate?


I imagine it would involve burning the sodium in air to form sodium peroxide, followed by reaction with water.

ecos - 24-11-2016 at 14:46

watch this: https://www.youtube.com/watch?v=ZqEWUw6sgpA

Jstuyfzand - 24-11-2016 at 14:48

Quote: Originally posted by Metacelsus  
Quote: Originally posted by Jstuyfzand  
Quote: Originally posted by ecos  
you can make H2O2 from Na.


Could you elaborate?


I imagine it would involve burning the sodium in air to form sodium peroxide, followed by reaction with water.


Would be pretty cost prohibitive, but I can see it working.

m1tanker78 - 24-11-2016 at 22:02

I've used sodium and potassium as getters. I store a lot of my solvents with sodium BBs in the bottles. In a pinch, aqueous sodium hydroxide can be prepared easily. It's inefficient but if you stock plenty of sodium it's not a big deal. I've prepared H2O2 from sodium peroxide but stabilizing it can be tricky and then you've got sodium contamination.

Sodium can be alloyed with other metals and then reacted away to create a high surface area version of the metal you alloyed.

ave369 - 25-11-2016 at 01:42

Not just hydrogen peroxide: anhydrous sodium peroxide itself can be made by burning sodium. This cannot be replicated by wet chemistry: the closest approximation that you can get in aqueous medium is sodium peroxide octahydrate, which is somewhat less useful.

NitratedKittens - 29-11-2016 at 02:22

You can use it to make biodiesel via sodium methoxide