when we mix citric acid with potassium solution. Its color change from purple to colorless.why?
Answers
Explanation:
The answer has two parts, and I’m going to have to change your question to define “an excess of citric acid”. I’ll tell you why below.
The first thing that happens is a classic KMnO4 redox reaction; the citric acid is oxidized and the permangate is reduced to MnO2. this normally forms a brown precipitate that indicates the reaction is proceeding.
Since citric acid has a very high oxygen balance already, the predominant result is mineralization to CO2. Now comes the interesting part, and the reason it goes clear instead of brown or even brown to clear. Citric acid (and citrate ion) is a reasonably good chelator for manganese dioxide, so as the reaction proceeds it complexes it in solution and prevents it from precipitating. Because there is no colour to the chelated solution it turns clear. This requires an excess of citric acid as there has to be enough left at the end to complex it all!
There’s another possible reaction as well, and that is that some of the permanganate is reduced all the way to Mn2+. This is a soluble, clear product and incidentally is what’s formed when you clean glassware after permanganate reactions using acidic hydrogen peroxide.
hope this helps u if yes then mark me brainest answer
plz
plz
plz.....
Answer:
Citric acid turns potassium permanganate from purple to colourless because it is a reducing agent.