Sciencemadness Discussion Board

Li in NH3 question

an_drip - 4-12-2015 at 02:52

Hello. I am no chemist. Sorry if this comes off as a stupid question, but I've done a bit of reading online about lithium metal dissolving in ammonia. I understand that lithium and other metals dissolve in liquid ammonia, but I have read elsewhere that someone had dissolved lithium in a NP solvent by bubbling ammonia gas through the NP, with lithium floating inside.

Therefore, are the gas bubbles somehow transitioning to liquid, before dissolving a bit of lithium at a time? Or does the gas itself dissolve the metal?

Thank you.

Detonationology - 4-12-2015 at 05:27

I assume that by "liquid ammonia," you are referring to common household ammonia (ammonium hydroxide), since ammonia is a gas at STP. In that case, sure it would dissolve, but most likely because of the water, probably not the ammonia! But lithium always dissolves in water making lithium hydroxide. I would guess to say that the formation of lithium hydroxide would occur faster in a solution of NH4OH compared to water, because there is an abundance of OH- ions to react with Li.

[Edited on 12-4-2015 by Detonationology]

ParadoxChem126 - 4-12-2015 at 05:45

I believe he is referring to lithium dissolved in liquified ammonia gas. It dissolves to give a solution of free electrons, which is employed in reactions like the Birch Reduction.

hissingnoise - 4-12-2015 at 05:50

Lithamide!

an_drip - 4-12-2015 at 05:52

Edit: Thanks, hissingnoise. From what I read, I'll assume that lithium amide can only be made using liquified ammonia, and that is what is probably happening when ammonia gas is bubbled through the NP. It must be turning to liquid under pressure.

Thanks for that answer. I failed to mention that I meant the anhydrous ammonia and not the household aqua ammonia solution. An example: I've read about people haphazardly throwing ammonia salts and lye into bottles, along with lithium metal floating on top of fuel, then getting the lithium to solvate. Usually doing something illegal and dangerous.

Is the ammonia gas transitioning to liquid under the pressure built in the bottle, thereby somehow mixing with the fuel and dissolving the lithium? Or are the gas bubbles doing the work on the lithium? As I said, I haven't studied chemestry, and am curious about what might be happening. Is it even possible for lithium to "dissolve" in gaseous NH3?

Search engine hasn't yielded much useful. Thanks again!

[Edited on 4-12-2015 by an_drip]

MrHomeScientist - 4-12-2015 at 15:07

There's at least one thread here on the subject: http://www.sciencemadness.org/talk/viewthread.php?tid=13161

Here's a good video too: https://www.youtube.com/watch?v=Eej6kG4NyFw

I don't think gaseous ammonia would do much to lithium metal; I've never heard of this reaction being done with anything other than liquid ammonia. In the video, the lithium gets a sort of bronze tint from the ammonia coming over, but I suspect that's from the gas condensing on the cold metal then reacting with it (rather than the gas directly reacting). Would be interested if anyone has seen anything different.

[Edited on 12-4-2015 by MrHomeScientist]

Crowfjord - 4-12-2015 at 16:05

In the same thread that you linked, Plastics reports making the lithium bronze at an ambient temperature of 10° C, so the reaction seems to work fine with gaseous ammonia. It took a while though, 10 hours.

[Edited on 5-12-2015 by Crowfjord]

cyanureeves - 4-12-2015 at 16:06

the video referred to in by the applied science video is this one by reaction factory. https://www.youtube.com/watch?v=PTT6qPKIijc that's it.thanx.
[Edited on 12-5-2015 by cyanureeves]

[Edited on 12-5-2015 by cyanureeves]

[Edited on 12-5-2015 by cyanureeves]

[Edited on 12-5-2015 by cyanureeves]

violet sin - 4-12-2015 at 17:54

https://www.youtube.com/watch?v=PTT6qPKIijc
Think you needed a space between any character, a period in this case, and the beginning of the link address. Or the end of the address.

Amos - 4-12-2015 at 18:00

Quote: Originally posted by Detonationology  
I assume that by "liquid ammonia," you are referring to common household ammonia (ammonium hydroxide), since ammonia is a gas at STP. In that case, sure it would dissolve, but most likely because of the water, probably not the ammonia! But lithium always dissolves in water making lithium hydroxide. I would guess to say that the formation of lithium hydroxide would occur faster in a solution of NH4OH compared to water, because there is an abundance of OH- ions to react with Li.

[Edited on 12-4-2015 by Detonationology]


If you don't understand the topic, you don't have to reply.

ParadoxChem126 - 4-12-2015 at 20:00

Quote: Originally posted by an_drip  
...I've read about people haphazardly throwing ammonia salts and lye into bottles...


Ammonium salts react with sodium hydroxide lye to make ammonium hydroxide and the corresponding sodium salt. Water is produced upon liberation of the ammonia gas from the ammonium hydroxide. Presumably, this water would react with the lithium before the ammonia was able to.

annaandherdad - 4-12-2015 at 21:34

You might want to look at the ammonia videos of Applied Science on youtube. He has made anhydrous ammonia and done everything with it from dissolving sodium in it to shrinking dollar bills.

But he could have made his liquid ammonia more efficiently. I would recommend making the ammonia gas by mixing dry NaOH and NH4Cl, drying the gas with KOH and liquifying it with dry ice. Use an inverted funnel in water to absorb any excess gas, so it doesn't come out in the room and choke you (although with dry ice you won't get that much).

That Applied Science guy has some very interesting videos, they're some of the best science videos I've seen. They are very informative.

Darkstar - 5-12-2015 at 23:03

Quote: Originally posted by ParadoxChem126  
Quote: Originally posted by an_drip  
...I've read about people haphazardly throwing ammonia salts and lye into bottles...


Ammonium salts react with sodium hydroxide lye to make ammonium hydroxide and the corresponding sodium salt. Water is produced upon liberation of the ammonia gas from the ammonium hydroxide. Presumably, this water would react with the lithium before the ammonia was able to.


He's referring to people making methamphetamine via the "shake 'n' bake" method. In that method, the lithium gets protected from water by a NP solvent (usually diethyl ether) that is less dense than water itself. The lithium floats on the top of the organic layer while the water stays below in the aqueous layer. The ammonia gas then bubbles up through the organic layer as it is produced.

Texium - 6-12-2015 at 08:26

Quote: Originally posted by Darkstar  
Quote: Originally posted by ParadoxChem126  
Quote: Originally posted by an_drip  
...I've read about people haphazardly throwing ammonia salts and lye into bottles...


Ammonium salts react with sodium hydroxide lye to make ammonium hydroxide and the corresponding sodium salt. Water is produced upon liberation of the ammonia gas from the ammonium hydroxide. Presumably, this water would react with the lithium before the ammonia was able to.


He's referring to people making methamphetamine via the "shake 'n' bake" method. In that method, the lithium gets protected from water by a NP solvent (usually diethyl ether) that is less dense than water itself. The lithium floats on the top of the organic layer while the water stays below in the aqueous layer. The ammonia gas then bubbles up through the organic layer as it is produced.
Yes, and from the "I am no chemist," cagey questions, and the specific interest in this one topic, it seems that perhaps the OP might be interested in doing his own shake 'n bake...

Yttrium2 - 6-12-2015 at 10:14

I think there is a difference between the lithium amide and the dissolved electrons. If the blue solution was poured into a non polar, I'm unsure what would happen as the ammonia would fizzle away. What would happen to the dissolved electrons of the lithium strip? Would lithium precipitate as the ammonia fizzles off?

ParadoxChem126 - 6-12-2015 at 22:42

Quote: Originally posted by zts16  
Yes, and from the "I am no chemist," cagey questions, and the specific interest in this one topic, it seems that perhaps the OP might be interested in doing his own shake 'n bake...


Pardon my cluelessness. Hopefully I did not provide assistance to any clandestine ambitions, that was not my intention.

[Edited on 12-7-2015 by ParadoxChem126]

MrHomeScientist - 9-12-2015 at 08:47

Quote: Originally posted by Crowfjord  
In the same thread that you linked, Plastics reports making the lithium bronze at an ambient temperature of 10° C, so the reaction seems to work fine with gaseous ammonia. It took a while though, 10 hours.

Indeed he did. That's what I get for not reading the thread fully. I stand corrected!