Question

Write the test by which following are distinguished:. Ethanol and acetaldehyde

Answer 1

Alcohol contains OH group and  Aldehyde contains CHO GROUP.

Alcohol on reacting with carboxylic acids undergo esterification reaction where as aldehyde will not undergo .

Aldehydes reduces tollen's reagent where as alcohol does not.

On warming with ammonical silver nitrate solution [tollen reagent ] in alkaline medium , aldehyde gives silver mirror on the side of test tube.

Fehlings Solution test only for Aldehydes:
Fehlings solution is alkaline solution of copper sulphate containing sodium potassium tartarate.Aldehydes gives reddish brown precipitate of Cu2) with Fehling solution.

Answer 2

Answer: To distinguish between the two, we add Tollen's reagent.

Explanation:

Ethanol is an alcohol (having function group -OH) and acetaldehyde is an aldehyde (having functional group -CHO).

To distinguish between the two functional groups, we add Tollen's reagent to both the solutions. The silver mirror is given by only aldehydes and alcohol will have no effect on adding Tollen's reagent.

The equations for the above is given below in the image.