sternman318
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Crystallization of KMnO4
Are there any viable routes to crystallizing potassium permanganate? It seems that it is so unstable that most routes would end up decomposing it. The
solution is pure, and of about 2% concentration( w/v, i believe)
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Mixell
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It decomposes at 240 C, I think you can evaporate the water slowly, without any decomposition. Just put in on the hotplate and turn the heat just
before the point where bubbles appeared, let it sit for a few hours, slowly turning the heat down as more and more water evaporates.
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Mixell
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Or if you don't want to evaporate all the way through, leave a concentrated solution and freeze it, crystals should form (KMnO4 is about 15 times more
soluble at 100C than at 0C).
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redox
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KMnO4 is not very stable in water, and your crystallized product will contain small amounts of MnO2 and KOH.
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