The reaction of amines with mineral acids to form ammonium salts shows that these are basic in nature. Aliphatic amines are stronger bases than ammonia whereas aromatic amines are weaker bases than ammonia. Aliphatic and aromatic primary and secondary amines react with acid chlorides, anhydrides and esters by nucleophilic substitution reaction. The main problem encountered during electrophilic substitution reactions of aromatic amines is that of their high reactivity. Substitution tends to occur at ortho- and para-positions. Hinsberg reagent is used for the identification and distinction between primary, secondary and tertiary amines. Aryldiazonium salts, usually obtained from arylamines, undergo replacement of the diazonium group with a variety of nucleophiles to provide advantageous methods for producing aryl halides, cyanides, phenols and arenes. Answer the following questions : (a) (i) Why $ ext{CH}_3 - ext{NH}_2$ is a stronger base than $( ext{CH}_3)_3 ext{N}$ in aqueous solution ? (ii) Write structural formulae of the compound A and B : $$ ext{CH}_3 ext{CONH}_2 \xrightarrow{ ext{NaOBr}} ext{A} \xrightarrow[ ext{Base}]{ ext{C}_6 ext{H}_5 ext{COCl}} ext{B}$$ (b) A compound 'X' with molecular formula $ ext{C}_3 ext{H}_9 ext{N}$ reacts with Hinsberg reagent to give a product insoluble in alkali. Identify 'X'. OR (b) How can you convert aniline to benzonitrile ? (c) Why is $- ext{NH}_2$ group of aniline acetylated before carrying out nitration ?

Year	Paper Code	Set	Position
CBSE 2026	Series 56-1	Set 1	Question 29
CBSE 2026	Series 56-1	Set 2	Question 30
CBSE 2026	Series 56-1	Set 3	Question 29

• Step 1: Stating the fundamental formula / law statement (+1 Mark)
• Step 2: Intermediate mathematical substitution or proof steps (+1 Mark)
• Step 3: Correct final value or conclusion with mandatory SI units (+1 Mark)