Spectacular experiment with Mn2O7

[budullewraagh]

you can. i'd imagine that reacting a permanganate with much more dilute sulfuric acid would yield permanganic acid. the only reason we get the anhydride upon reacting permanganate with conc sulfuric acid is that the H2SO4 dessicates the resulting HMnO4.

[woelen]

Sodium permanganate and lithiumpermanganate are not really different from potassium permanganate. The main difference will be the solubility in water and the level of hygroscopic behavior. Sodium permanganate can be obtained commercially, but it is hardly used, due to its hygroscopic properties. The only place, where sodium permanganate is used instead of potassium permanganate is where with the potassium salt the concentration of an aqueous solution cannot be sufficiently high.

[YT2095]

but Lithium (as I figure may be the more interesting) has unusual properties in that upon Thermal decomp, it often displays characteristics uncommon to the other group 1 elements.

[bob000555]

It would be cool if you try this with some citric acid powder yielding acetone witch also be oxidized. Also try some concentrated acetic acid(I make mine by distilling cheep vinegar). With the sulfur experiment perhaps try heating it.

[aj47]

I too tried this experiment last night and had alot of fun testing out various substances. I found most organic materials were easily oxidised but with metal powders i.e. Mg, Al and Fe there was no reaction. This suprised me giving how easily oxidised the metals are with weaker oxidizing agent agents i.e. KNO3, KMno4. Does anyone know why this is? Could it be a structure thing like sulphur?

[jdurg]

Could be that the really easily oxidized metals already had a protective layer of oxide on them which prevented any further reaction.

[aj47]

I would have thought the solution would be acidic enough to break down these layers, especially for iron and magnesium.

[woelen]

I noticed that metals like Mg and Al do not react with concentrated H2SO4. Only when some water is added, the reaction starts, and then it becomes really violent. Probably a similar thing is true for the H2SO4/KMnO4 mixes.

[aj47]

Interesting thanks.