Manganese Heptoxide: Synthesis and Reactions

In this video, we create a small quantity of manganese (VII) oxide, also known as manganese heptoxide or Mn2O7, and react it with a combustible organic compound, our old combustible organic standby, denatured ethanol.

The reactions seen here are:
2*KMnO4 (s) + H2SO4 (aq) → Mn2O7 (l) + K2SO4 (aq) + H2O (l)
2*Mn2O7 (l) + C2H5OH (l) → 4*MnO2 (s) + 2*CO2 (g) + 3*H2O (g)

It is very important that eye and hand protection are worn at all times during the course of this experiment. This reaction involves a very concentrated strong acid, as well as powerful oxidizing reagents that must be handled with care and treated with respect. A respirator is also recommended to prevent the inhalation of the manganese-based fumes coming off of this reaction.

Potassium permanganate is a DEA classified List II chemical. As such, only a limited quantity (One pound) may be legally purchased annually in the USA. You may find this chemical stocked at most online retailers specializing in scientific supply, but sold under strict quantity control.

Sulfuric acid, the world's most important chemical in terms of quantity produced per year, is also one of the hardest for the consumer to buy. The Reaction Factory recommends Rooto brand professional strength drain cleaner- look to make sure it's labeled as containing concentrated sulfuric acid.

Denatured alcohol can be purchased at any hardware store alongside paint thinners and other solvents. The alcohol is denatured, which is to say, adulterated with other toxic solvents such as methanol and kerosene, to make it unfit for drinking and therefore avoid a federal excise tax on alcohol sold for human consumption. Never attempt to drink this at any concentration due to the overall toxicity.

Category:

Science & Technology

Tags:

• manganese
• heptoxide
• (VII)
• seven
• oxide
• VII
• oxidizer
• oxidation
• reaction
• burn
• flames
• flammable
• sulfuric
• acid
• alcohol
• ethanol
• denatured
• Mn2O7
• H2SO4
• CH3CH2OH
• C2H6O

[endimion17]

I can not believe how stupid some people can be. You NEVER EVER drop combustibles in manganese heptoxide, especially not in a mixture of the heptoxide and concentrated sulfuric acid. You could've been sprayed with the mixture, and it EATS SKIN and it does it PROMPTLY. It is similar to a warm piranha solution. It eats skin and those wounds stay forever.

A man would think that people doing more complex experiments would know what not to do in this classic experiment. But I was wrong.

[ReactionFactory]

@endimion17

Well somehow, we both survived this experiment, which is apparently not supposed to happen. I sincerely hope you choose to forgive us.

[Caswalle]

this is so weird i can and have bought potassium permanganate buy a local store and i can get battery acid and together they will make that!!!

[ReactionFactory]

@Caswalle

I'm not sure that battery acid is concentrated enough to dehydrate the permanganic acid to manganese heptoxide. No matter, the sulfuric acid you're looking for is sold as drain opener!

[RenXiS47]

Can you explain something thats bugging me:

oxidizer (Mn2O7) + primary alcohol ---> aldehide + water ; why isnt this the case here? Instead you get: CO2 + water

[ReactionFactory]

@RenXiS47

We're talking about totally different strengths of oxidizer here. In terms of which compounds it can oxidize, to what extent it can oxidize them, the rate it which the oxidation occurs, and the energy released by the oxidation reaction, manganese heptoxide is far more powerful than the oxidizing agents that you're thinking of.

[trick58]

Hey guys, I appreciate your enthusiasm - I was doing these sames kinds of experiments at a young age and it helped me catch the science bug.. I do caution you to be a bit more careful. The spattering you see is a real problem and these chemicals can cause permanent damage. You also want to pay a bit more attention to your naming - Mn is a transition metal, so you have to use the Stock or Classical system to name it-using the Greek prefix on the oxygen just mixes it up with nonmetal/nonmetals.

[zmod101]

remember adehydes can be further oxidixzed thats what your missing here.

[Spaceshotx7]

when it reacts, how is the fire created? How does it create heat with the chemical?

[atourdeforce]

@chemlabchemistry of coarse it was oxidised it is an organic compound, you should of known the outcome before you started.

[chemlabchemistry]

Im sorry but it is stupid to make such a large amount of Mn2O7. It is actually explosive and ignites the skin when contacted. I did it as well on my channel but with much smaller amounts. A fellow amateur chemist once got a drop of green oil on his skin and was badly burned. I have also done some stupid things doing home chemistry, you learn from it, but not with things like Mn2O7.

I also tried some experimenting with Mn2O7, like extracting it in CCl4, but this is even oxidised. Small scale!

[PersonguydudeWB]

@endimion17

You do realize that a lot of common chemicals, acids and such, that are used in a lab destroy or otherwise dehydrate organic compounds? I am sure the maker of this video was wearing proper safety gear.