A bottle containing a standard solution of KMnO4 is found to have brown stains on the inside. Why will this KMnO4 be of no further use for quantitative experiments?
2 answers
The brown specks/stains are MnO2 which shows the decomposition of the KMnO4. Unfortunately, once started, the MnO2 catalyzes the further decomposition of the solution. Filtering it will not get the tiniest specks out. Best to discard.
yuh
1 answer