[Donaldson Tan]

Anyway, here is the standard electrode potential for Na and Ca:
Na+ + e <=> Na(s); E = -2.714V
Ca2+ + 2e <=> Ca(s); E=-2.866V

Given these data, what do u all think?

[AWK]

Using Ca for obtaining Na from NaCl is possible only in the case when temperature is above boiling temperature of Na and Na is removed from reaction mixture ie over 900 C up to 1400 C.

AWK

[Seymor-Omnis]

you can but sodium hydroxide, which is lye from a drugstore, you can get copper wire for an electrode at a hardware store and a 9v battery is found most anywhere.

I can't stress how dangerous this is. The sodium that is made can spontaneously catch on fire from the heat generated in this reaction. If you are going to do this, only use a view pellets of Sodium hydroxide and make a few milligrams of sodium to begin with.

If you want sodium you can get it from a chemical distributor or even off e-bay these days.

Ok, lets just forget the method of obtaning sodium the way I mentoned  .
Is there any "special" circumstances that need to be obtained to sodiu by means of electrolysis of lye?

[Donaldson Tan]

CaCl2 + 2Na => 2NaCl + Ca
Calcium can be synthesised in small scale according to the reaction abovementioned. It seems to be of reverse nature to the reaction in topic.

Hmm.. Ca melts at 842 degree celcius. Sodium boils at 883 degree celcius. NaOH melts at 318 degree celcius. Unless the molten state of Ca contributes to the reaction, in the sense that the presence of "sea of electrons" has a significant impact on the reaction pathway that it would differ from the usual dispalcement reaction.

I suppose NaOH would dissolve in molten Ca and we wont be able to differentiate sodium metal from calcium metal cuz the sea of electron now no longer belongs to Ca exclusively. Then at temp above 883 degree celcius, sodium would atomise and boil off.

I am just speculating. Pls somebody enlighten me =D

[Seymor-Omnis]

I looked up the metal reactivity series, and it stated the order was Li, K, Ca, Na, Al...  So, according to this order calcium is more reactive.

The only reason I can think of why this order would be incorrect is the copywrite of this book I looked it up in was 2002, might be outdated...

[nfstanley]

you can but sodium hydroxide, which is lye from a drugstore, you can get copper wire for an electrode at a hardware store and a 9v battery is found most anywhere.

I can't stress how dangerous this is. The sodium that is made can spontaneously catch on fire from the heat generated in this reaction. If you are going to do this, only use a view pellets of Sodium hydroxide and make a few milligrams of sodium to begin with.

If you want sodium you can get it from a chemical distributor or even off e-bay these days.

Here is a link to my article "Make your own sodium" from the Amateur Scientists Bulletin (Society of Amateur Scientists).

<http://www.sas.org/E-Bulletin/2001-10-05/chem/column.html>

Do be careful and observe the precautions detailed in the article.

Norm

[Donaldson Tan]

I looked up the metal reactivity series, and it stated the order was Li, K, Ca, Na, Al...  So, according to this order calcium is more reactive.

The only reason I can think of why this order would be incorrect is the copywrite of this book I looked it up in was 2002, might be outdated...

Ya.. the order is incorrect~

[Mitch]

Norm, that is an excellent resource, thank you for sharing. I'm a big fan of the SAS.

[Scratch-]

This guy made sodium in his garage with a blowtorch, table salt and some calcium chloride. Using calcium chloride you can get the melting temp down to about 600 degrees Celsius, a bit hotter than NaOH but the fumes and splashes (while still hazardous) aren’t as dangerous. Here is the post where he talks about it:

"The device I want to sell is for the electrolysis of water. The method I made to get sodium was rather crude but worked (suprisingly). The result was of a low grade of course. I didn't know much about Downs cells but I still took steps to prevent oxidization.

I heated a mixture of NaCl (table salt) and CaCl2 (calcium chloride- from chemistry set) to its melting point in an old crucible my dad had with his torch. I lowered in two carbon rods (suspended from copper wire) and placed a steel washer blank over the whole setup to keep out SOME air. The sodium (and calcium too apparently) collected on the cathode. When I felt I had a fair amount I pulled the cathode and shook it off inside an aluminum tube. I let this cool for about a second or two then proceeded to pour on mineral oils to keep out oxygen.

I put some of the chips of sodium in a petri dish of water and they bounced around. I think I may have found the simplest version of your steam boat! My question is how does pure sodium react? Is it supposed to burn? I would like to see any ideas you have on a Downs Cell but my washer was a pretty close fit to the molten mixture. I used an old Hawker SLA battery I had lying around (8 Ah, I think it cranked at 250 amps once....) and had 2 dehumidifiers running in close proximity (doubt that helped). And yes, I used the calcium chloride to lower the melting temperature (though I could use plain NaCl if I used more Oxygen with my torch...) I will take pictures if I ever do it again. By the way- my science teacher told me of an incident where a teacher put a brick of pure sodium in a garbage can of water resulting in many casualties. Have you heard of this incident? Anyway, thank you."

Some of it is about another conversation.

Heres the rest of the page:
http://scitoys.com/board/messages/9/49.html?1081036047

[gregpawin]

Actually, I can't imagine someone retarded enough to do something like putting a brick of sodium in a garbage can...  I would think its a myth though, since for there to be casualties, there probably implying some sort of explosion.  Maybe powdered sodium metal... although I'm not sure that's possible with the oxidation... and sodium isn't the most explosive alkali metal either...  

[Scratch-]

Of course you have to take into account the brick actually melting and being broken into pieces in the reaction of the outer layer of sodium, then the rest all reacting at once. It would probably depend on the size of the brick, I think most suppliers sell one pound bricks.

[Mitch]

I too would doubt any science teacher is that stupid.

[Scratch-]

I wonder if the teacher won a darwin award.  

[jdurg]

I doubt that ever happened.  What I can guarantee is that the one pound brick did not fully react.  What happens when sodium reacts with water is that the outer surface reacts with the water, generating heat and allowing more sodium to react.  Eventually, the heat builds up enough to melt the sodium a bit which then causes the reaction to exponentially increase in speed.  This causes a bit of an explosion which would shoot what's left of the brick high into the air, and molten sodium metal would also be flung away.  There's no way the entire brick reacted.