Hawkguy
Hazard to Others
Posts: 326
Registered: 10-10-2014
Location: British Columbia (Canada eh!)
Member Is Offline
Mood: Body is Ready
|
|
Strange Permanganate (?)
Bought 500g Potassium Permanganate from 'Busy Bee Chemistry', an Ebay seller (Canadian). Advertized in the photo as pure looking purple - black
crystals, I was a bit disappointed. Its a purple powder, with bits of black and brown (paper or pulp? splinters?) and seems like it has been 'cut'
with something. I know technical grade isn't the best, but this is still a letdown. Additionally, there are two things that get to me. Although I have
been doing plant extractions in the garage for a few weeks now, the solution in water smelled a bit sweet/ fruity, I don't know if that was just my
imagination. As well, when I tried the classic Glycerin + Potassium Permanganate (with water for acceleration), it would only fizzle and smoke, it
took three tries and a lot of Permanganate to get any real flames to appear, and even that was a bit lame. (A short, 1.5 - 2 second burst of flame.) I
don't know what I was expecting from the product, maybe this is normal and I've watched too many youtube videos. Does anyone have any experience
related or method for me to test the material? Gee
|
|
|
j_sum1
Administrator
Posts: 6221
Registered: 4-10-2014
Location: Unmoved
Member Is Offline
Mood: Organised
|
|
Glycerine and permanganate is a bit dependent on the crystal size. In my school lab we have a jar of the stuff that just won't go. (The source of a
few dud thermite ignitions before we figured out what was happening.) This jar is actually labelled analytical grade. The crystals are large and the
glycerine just won't wet it well.
I am not sure of the best test to do to ascertain the purity. But I would not assume the worst.
|
|
|
DraconicAcid
International Hazard
Posts: 4278
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
Ditto with the crystal size. If you grind it up in a mortar and pestle before mixing in the glycerol, it works much better (or so I have heard).
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
Look up a recipe for 0.01 M KMnO4, prepare a small amount and check it for insoluble matter (MnO2, usually).
|
|
|
Molecular Manipulations
Hazard to Others
Posts: 447
Registered: 17-12-2014
Location: The Garden of Eden
Member Is Offline
Mood: High on forbidden fruit
|
|
Quote: Originally posted by Hawkguy  | | Advertized in the photo as pure looking purple - black crystals, I was a bit disappointed. Its a purple powder [...]
|
Emphasis mine.
I'd say try recrystalizing it in case. Since it has some potassium permanganate, make a hot saturated solution, filter the other shit and cool and
grow in an ice bath, at least twice should be alright.
-The manipulator
We are all here on earth to help others; what on earth the others are here for I don't know. -W. H. Auden
|
|
|
Pasrules
Hazard to Self
Posts: 78
Registered: 4-1-2015
Location: Yellow Cake Deposit
Member Is Offline
Mood: Lacking an S orbital
|
|
In Australia you can get high purity KMno4 from any chemist as an antiseptic, crystal size is small and comes in 50g containers. I use it to give
sparklers that extra kick. Oh and to oxidize/indicate aconitic acid
Atropine, Bicarb, Calcium.
|
|
|
papaya
National Hazard
Posts: 615
Registered: 4-4-2013
Member Is Offline
Mood: reactive
|
|
Red-ox titration will tell you if it's cut or not, you can use oxalic acid for that.
|
|
|
TGT
Harmless
Posts: 46
Registered: 9-11-2014
Member Is Offline
Mood: No Mood
|
|
I get my potassium permanganate from those keep fresh packages to keep veggies in the fridge longer. They are expensive to buy, but if you look in
the new fridge department at any large freezer store they have them as free samples. I just grab them all and call it a day lol. They are food grade
potassium permanganate so the quality is very high. I have noticed though the colour is dark purple, a little lighter than the black powder I see on
you tube, but it has always worked great for me.
Also, the potassium permanganate glyserin reaction is very dependant on ambient temperature. In the summer it reacts violently, but any temp under 15
or so degrees celcius the reaction is slower. In winter it will sometimes not react at all. I know this because some camping types use it as a fire
starter and were very disappointed when cool out the reaction was not impressive.
TGT
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
