Question

when is KMnO4 used?

Answer 1

KMnO4 is an oxidiing reagent which can be used for various purpose.

1) It is used to eliminate iron and H2S from well water

2) The main use of KMnO₄ is as a reagent for the synthesis of organic compounds

Alkene can be converted into 1,2 diols in mild condition  

Alkene can be cleaved to carboxylic acids in acid condition

Benzylic positions can be oxidized to carboxylic acid

3) In inorganic chemistry it can be used to determine the total oxidisable organic material in an aqueous sample

Further it can be used as Fruit preservation, In Survival kits.