Sciencemadness Discussion Board

KMnO4 + Glycine

gatosgr - 13-5-2015 at 06:08

Hey guys why does reacting KMnO4 with glycine form something like a carbon foam and how does the reaction takes place?


Also is there any way to save a degrading KMnO4 reagent? I've noticed there are some brown stains on the container which probably are MnO2?


[Edited on 13-5-2015 by gatosgr]

blogfast25 - 13-5-2015 at 07:40

Quote: Originally posted by gatosgr  
Hey guys why does reacting KMnO4 with glycine form something like a carbon foam and how does the reaction takes place?

Also is there any way to save a degrading KMnO4 reagent? I've noticed there are some brown stains on the container which probably are MnO2?


Describe the conditions. This is a forum about amateur science, not a plenum of mind-readers.

"Carbon foam"?

gatosgr - 13-5-2015 at 07:55

It looks like carbonization. Conditions atp... I dont know molar concentrations I just dropped some water in the mix.


[Edited on 13-5-2015 by gatosgr]

blogfast25 - 13-5-2015 at 08:13

"atp"?

I think the black may be MnO2: reduction of permanganate in neutral/alkaline conditions.

[Edited on 13-5-2015 by blogfast25]

gatosgr - 13-5-2015 at 08:21

atmospheric temperature and pressure=atp

Damn MnO2 is insoluble in water..how do I filter it out?

blogfast25 - 13-5-2015 at 10:41

Quote: Originally posted by gatosgr  
Damn MnO2 is insoluble in water..how do I filter it out?


Errrm... with a filter?

Amos - 13-5-2015 at 11:26

I'm going to go out on a limb here and guess that you meant to say glycerin, and not glycine, the amino acid.

Pumukli - 13-5-2015 at 11:41

But don't use filter paper!
KMnO4 and filter paper (actually any paper) just generates more MnO2. And if you try to remove that by filtering again on another filter paper... :-)

Maybe that carbon like foam is not carbon at all but wet MnO2 and entrapped CO2 bubbles from the oxidation of glycine. Permanganate oxidizes glycine and in neutral environment (you used water not an acid to wet the mixture) the oxydation ends at MnO2 and not at Mn(2+).
Maybe you can purify some "carbon" from the foam and decide (test) if it is real carbon or MnO2.

blogfast25 - 13-5-2015 at 11:44

Quote: Originally posted by Amos  
I'm going to go out on a limb here and guess that you meant to say glycerin, and not glycine, the amino acid.


Good point, I think.

gatosgr - 13-5-2015 at 11:59

Ofcourse I mean the amino acid... Pumukli I think is correct I should try to purify the mixture as much as I can and figure out if it's carbon or MnO2, thanks for the answers.:D

[Edited on 13-5-2015 by gatosgr]

zed - 13-5-2015 at 14:30

Shooting for Nitromethane?

gatosgr - 14-5-2015 at 04:16

No not really but I found out what you're talking about.:D

http://www.sciencemadness.org/talk/viewthread.php?tid=7491

https://www.sciencemadness.org/whisper/viewthread.php?tid=29...

[Edited on 14-5-2015 by gatosgr]