Question

Chemical reaction of aldehydes and ketones.

Answer 1

Both the aldehyde and ketone group has carbonyl group, i.e., $>C=O$ group and they give many chemical reactions like Nucleophilic addition reaction, reduction reaction, oxidation reaction, halogenations, and reaction with alkalis.

Complete answer:
Some chemical reaction of aldehydes and ketones are:
(i)- Addition of hydrogen cyanide:
Acetaldehyde in reaction with hydrogen cyanide gives acetaldehyde cyanohydrins. The reaction is:

Acetone in reaction with hydrogen cyanide gives acetone cyanohydrins. The reaction is:

(ii)- Addition of Grignard reagent:
Formaldehyde when reacted with Grignard reagent produces primary alcohol. The reaction is given below:

Acetaldehyde when reacts with Grignard reagent, it produces secondary alcohol. The reaction is given below:

Acetone when reacts with Grignard reagent, it produces tertiary alcohol. The reaction is given below:

(iii)- Addition of ammonia derivative:
Aldehyde or ketone when reacted with ammonia derivatives forms a group containing $-C=N-$ group.

(iv)- Reduction reaction:
Aldehydes or ketones on reduction gives respective alcohols in the presence of platinum or palladium and their reactions are given below:
$RCHO\to RC{{H}_{2}}OH$
$>C=O\to \,>CHOH$
The reduction can be done by many catalysts like zinc-amalgam, hydrazine and potassium hydroxide, and hydriodic acid, and red phosphorus.
(v)- Oxidation reaction:
Aldehydes and ketones on oxidation form respective carboxylic acids. The reactions are given below:

(vi)- Halogenation reaction:
Aldehydes and ketones also give halogenations reaction as given below:

(vii)- Reaction with alkalis:
Aldehydes and ketones in the presence of dilute sodium hydroxide give aldols. These reactions are given below:

Note:
The reaction of aldehydes and ketones with alkalies is known as an aldol condensation reaction. Aldehydes and ketones show so many chemical reactions because they are very reactive.