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Ryan Arlis

Wed Jul 18 2007, 11:14PM

Registered Member #577 Joined: Sun Mar 11 2007, 11:48PM
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Posts: 26

http://view.break.com/333907

...

Thu Jul 19 2007, 01:20AM

Registered Member #56 Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445

shikes!

Kids lucky it didn't get started faster... Or explode...

Sulaiman

Thu Jul 19 2007, 01:55AM

Registered Member #162 Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140

I remember doing this with potassium permanganate and glycerine as a youth

just as with antifreeze it takes a while to start -not that dangerous really.

Simon

Fri Jul 20 2007, 05:34AM

Registered Member #32 Joined: Sat Feb 04 2006, 08:58AM
Location: Australia
Posts: 549

I can't watch the video here but I doubt they were being safe enough.

Permanganate mixtures are so unreliable.

Dave Marshall

Fri Jul 20 2007, 06:04AM

Registered Member #16 Joined: Thu Feb 02 2006, 02:22PM
Location: New Wilmington, PA
Posts: 554

Ask Chris F. about his (and mine, and Grant's) lesson about potassium permanganate and sugar. Word of advice...Don't mix it in a water bottle cap.

Dave

AndrewM

Fri Jul 20 2007, 05:36PM

Registered Member #49 Joined: Thu Feb 09 2006, 04:05AM
Location: Bigass Pile of Penguins
Posts: 362

Also from the annals of personal experience: do not sand a block of permangante/epoxy mixture with a dremel tool.

Yeah, I know, admitting that takes me down a notch.

Shaun

Mon Jul 23 2007, 03:43AM

Registered Member #690 Joined: Tue May 08 2007, 03:47AM
Location: New Jersey, USA
Posts: 616

What do you use a permanganate/epoxy mixture for? And isn't the KMnO4 and Glycerine mix supposed to be good for igniting thermite? From the looks of the video is seems fun enough by itself...

Swany

Thu Jul 26 2007, 08:36PM

Registered Member #261 Joined: Mon Feb 27 2006, 12:34AM
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Posts: 22

Yeah, it ignites thermite, but really, there are better ways to go about it IMHO. The leftovers contaminate the thermite and it is messy. Permagnate stains like none other (exept for nitrophenol diazo derivs, which have yet to come off of my countertop, 3 years later).

It is a fun mix. I just aquired a lot of sodium, so I will be preparing some sodium peroxide which tends to ignite on contact with fuels. Fun fun fun for everyone.

Almost forgot; permagnate and glycerin is fun, but manganese heptoxide is that much better. Permagnic acid anhydride, Mn2O7, the stuff is truely the devil. Prepared by dissolving KMnO4 in concentrated H2SO4, I will post more about it later, but belive you me, it is truely awsome.

Chris

Thu Jul 26 2007, 11:21PM

Registered Member #8 Joined: Thu Feb 02 2006, 04:34AM
Location: Harlowton, MT, United States
Posts: 214

Mn2O7 is a highly unstable and explosive compound, which is to be made and used very cautiously at one's own risk. It explodes if heated to 55C so don't even think about trying to distill it. You really need to mention such points when apparently suggesting the use of such a compound. Even though this information is available to anyone who looks for it, you can't count on people doing that, and this substance is no joke.

Swany

Fri Jul 27 2007, 06:29AM

Registered Member #261 Joined: Mon Feb 27 2006, 12:34AM
Location:
Posts: 22

Distilling it would be a bad, bad, bad idea indeed. Mn isn't meant to be stable in such oxidation states, what goes up must come down!

Oxygen-containing acids condensation products stability is inversely proportional to the acid strength. That is, HClO4 and HMnO4 (both very scary in their own right, stability issues and first acid constants of about 10^8) condense to form large molecules (Cl2O7, Mn2O7) with serious difficulty. H2SO4 can be condensed to form H2S2O7, phosphoric acid forms loads of condensation products in solutions. But I digress, point being, Mn2O7 in any form is not stable!

Mn2O7 prepared by dissolving permagenate in conc. sulfuric acid is not pure; it is in sulfuric acid solution. It will seperate as oily, green drops, but they are still not pure. Brauer outlines the production of pure Mn2O7, 2 eq. KMnO4 (crystalline, ultra-pure for obvious reasons) and 2 eq. H2SO4. Add KMnO4 over a period of 15 minutes to form a slurry, cover and set aside overnight. Solids will form and the Mn2O7 oil is gently kneeded out of the formed stuff with a mortar and pestle... sounds scary!

The stuff decomposes into MnO2 and O3, if you do not cool the former reaction or add slowly enough, purple fumes will evolve into a volcano of porous brown MnO2 and O3.

Really though, it is a very amusing -if not highly dangerous- novel explosive. Drips on kleenex is a personal favorite...

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