is KMnO4 the molecular formula for Acidified dilute potassium permanganate
KMnO4 is potassium permanganate.
Another way the question could be asked might be, "Is KMnO4 the salt of a weak acid, HMnO4, and if you acidify a dilute solution of the salt, would this regenerate the acid form?" We have been educated to not think so, but thinking logically, the question seems to be a good one.
pKa around -0.3
I would say answer is - no. pH of the solution will be almost perfectly neutral.
so what should i write for the molecular formula of Acidified dilute potassium permanganate?
There is no single molecular formula. This is not a compound - this is a mixture.
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