Question

1. Aldehydes and ketones are carbonyl compounds Give a test for identication of aldehydes.

2. Acidic strength is related to the stability of carboxylate anion. Which acid of each pair is stronger?

i. CH₃COOH or CH₂FCOOH

Answer 1

1. Benedict test. Benedict reagent is a mixture of sodium carbonate and sodium citrate. This on reaction with aldehyde gives red precipitate of Cu₂S.

2. Acidic strength is related to the stability of carboxylate anion.

Acid of each pair is stronger: 

(i) CH₂FCOOH. This is due to the high electron with drawing effect of F.

This is due to the high electron with drawing effect of the -CF₃ group.