Consider the following sequence of reactions to give the major product (X) (reaction scheme shown) P g of the major product ( X ) formed is reacted with $\mathrm{NaHCO}_{3}$ soluion to liberate a gas which occupied $11.2 \mathrm{dm}^{3}$ at STP. $\mathrm{P}=$ ______ . g. (Given molar mass in $\mathrm{g} \mathrm{mol}^{-1}$ H: 1, C: 12, O: 16, Cl: 35.5)

JEE Main · 2026 · 04 Apr 2026 · Shift 1 · Hydrocarbons

Consider the following sequence of reactions to give the major product (X)

(reaction scheme shown)

P g of the major product ( X ) formed is reacted with

NaHCO_{3}

soluion to liberate a gas which occupied

11.2 dm^{3}

at STP.

P =

______ . g.
(Given molar mass in

g mol^{- 1}

H: 1, C: 12, O: 16, Cl: 35.5)

Answer: 78

Solution

Benzene undergoes Friedel--Crafts methylation with

CH X_{3} Cl / AlCl X_{3}

to give toluene; ring chlorination with

Cl X_{2} / FeCl X_{3}

gives mainly

p

-chlorotoluene; oxidation of the methyl group with

K X_{2} Cr X_{2} O X_{7} / H X_{2} SO X_{4}

gives

p

-chlorobenzoic acid, the major product X, of molar mass

7 (12) + 5 (1) + 2 (16) + 35.5 = 156.5 g mol^{- 1}

. As a carboxylic acid, one mole of X liberates one mole of

CO X_{2}

with

NaHCO X_{3}

. The gas measures

11.2 dm^{3}

at STP, i.e.

\frac{11.2}{22.4} = 0.5 mol

, so

0.5

mol of X reacts. Its mass is

P = 0.5 \times 156.5 = 78.25 g

, which to the nearest integer is

78

JEE Main · 2026 · 04 Apr 2026 · Shift 1 · Integer answer

Practise more: all JEE Main PYQs on Hydrocarbons →

JEE Main · 2026 · 04 Apr 2026 · Shift 1 · Hydrocarbons

Solution

More JEE Main questions on Hydrocarbons