Question

3 ml of ethanol is taken in a test tube and warmed gently in a water bath .a 5% solution of alkaline potassium permanent is added first drop by drop to this solution then in excess. 1) how is 5% solution of KMNO4 prepared ?​

Answer 1

Answer:

Explanation:

Correct statement:

Take about 3 mL, of ethanol is a rest tube and warm it gently in a water bath.

(ii) Add a 5% solution of alkaline potassium permanganate drop by drop to the solution.

(iii) What happens to the colour of KMnO4 added initially and then in excess? Give reason. Name the product of this reaction.?

Solution:

• The purple colour of alkaline potassium permanganate solution, also known as Baeyer's reagent gets initially discharged.
• On adding the reagent excess, the purple colour persists. Actually, Baeyer's reagent is an oxidising agent.
• It provides oxygen to oxidise ethanol to ethanoic acid. Once the oxidation is complete, the further addition of Baeyer's reagent imparts the purple colour to the solution.

Reaction is given below:

CH3CH2OH Ethanol + 2(O) released from oxidising agent → CH3COOH Ethanoic acid + H2O