
In the reaction , B is :
a.) benzoic acid
b.) benzoyl chloride
c.) benzaldehyde
d.) chlorobenzene
Answer
140.1k+ views
Hint: The first reagent given is the methyl chloride in the presence of aluminium trichloride. It functions in alkylation of the compound while the second reagent functions in oxidation of the compound. The answer to this question is a carboxylic acid with molecular mass 122 g. This is because the ultimate product of oxidation of alkyl is the acid.
Complete step by step solution:
Let us move step by step in the reaction to get the correct product.
We have the initial reactant benzene. We know that benzene is electron rich in nature. It is even highly stable due to resonance and thus it does not let resonance chain break. So, it does not give addition reactions.
It can very easily give aromatic electrophilic substitution reactions.
The first reagent is the methyl chloride in the presence of aluminium trichloride. It is an alkylation reaction where benzene gets converted into toluene and HCl is released as a byproduct. The A product formed is toluene. This reaction is Friedel Crafts alkylation. The reaction can be written as -

This reaction involves following mechanism-
The methyl chloride reacts with aluminium chloride to give carbocation. This methyl carbocation is an electrophile and this gets attached to benzene.

This carbocation is stabilised by resonance as-

The hydrogen is eliminated restoring resonance.

The second reagent that acts on toluene is potassium permanganate. The potassium permanganate is used for oxidation and here also, it does oxidation of the methyl group of toluene.
The oxidation is the addition of oxygen or removal of hydrogen. Here, the oxygen will get bonded with carbon and result in the formation of Benzoic acid. The benzoic acid is the product B.
The answer can-not be benzaldehyde because the potassium permanganate is a very strong reagent and it converts the benzaldehyde formed into benzoic acid. Firstly, from toluene benzaldehyde is formed which later gets converted into benzoic acid.
The reaction for this is as -

So, the answer is option a.)
Note: It must be noted that alkylation means the addition of alkyl groups. As here, the reagent was methyl chloride; this means the reagent had a methyl group. So, the methylation occurred. If it would have been ethyl chloride along with aluminium trichloride, the ethylation would have occurred.
Complete step by step solution:
Let us move step by step in the reaction to get the correct product.
We have the initial reactant benzene. We know that benzene is electron rich in nature. It is even highly stable due to resonance and thus it does not let resonance chain break. So, it does not give addition reactions.
It can very easily give aromatic electrophilic substitution reactions.
The first reagent is the methyl chloride in the presence of aluminium trichloride. It is an alkylation reaction where benzene gets converted into toluene and HCl is released as a byproduct. The A product formed is toluene. This reaction is Friedel Crafts alkylation. The reaction can be written as -

This reaction involves following mechanism-
The methyl chloride reacts with aluminium chloride to give

This carbocation is stabilised by resonance as-

The hydrogen is eliminated restoring resonance.

The second reagent that acts on toluene is potassium permanganate. The potassium permanganate is used for oxidation and here also, it does oxidation of the methyl group of toluene.
The oxidation is the addition of oxygen or removal of hydrogen. Here, the oxygen will get bonded with carbon and result in the formation of Benzoic acid. The benzoic acid is the product B.
The answer can-not be benzaldehyde because the potassium permanganate is a very strong reagent and it converts the benzaldehyde formed into benzoic acid. Firstly, from toluene benzaldehyde is formed which later gets converted into benzoic acid.
The reaction for this is as -

So, the answer is option a.)
Note: It must be noted that alkylation means the addition of alkyl groups. As here, the reagent was methyl chloride; this means the reagent had a methyl group. So, the methylation occurred. If it would have been ethyl chloride along with aluminium trichloride, the ethylation would have occurred.
Recently Updated Pages
JEE Main Participating Colleges 2024 - A Complete List of Top Colleges

JEE Main Maths Paper Pattern 2025 – Marking, Sections & Tips

Sign up for JEE Main 2025 Live Classes - Vedantu

JEE Main 2025 Helpline Numbers - Center Contact, Phone Number, Address

JEE Main Course 2025 - Important Updates and Details

JEE Main 2025 Session 2 Form Correction (Closed) – What Can Be Edited

Trending doubts
JEE Main 2025 Session 2: Application Form (Out), Exam Dates (Released), Eligibility, & More

JEE Main 2025: Derivation of Equation of Trajectory in Physics

JEE Main Exam Marking Scheme: Detailed Breakdown of Marks and Negative Marking

Learn About Angle Of Deviation In Prism: JEE Main Physics 2025

Electric Field Due to Uniformly Charged Ring for JEE Main 2025 - Formula and Derivation

JEE Main 2025: Conversion of Galvanometer Into Ammeter And Voltmeter in Physics

Other Pages
NCERT Solutions for Class 12 Chemistry Chapter 6 Haloalkanes and Haloarenes

NCERT Solutions for Class 12 Chemistry Chapter 2 Electrochemistry

NCERT Solutions for Class 12 Chemistry Chapter 7 Alcohol Phenol and Ether

NCERT Solutions for Class 12 Chemistry Chapter 1 Solutions

Solutions Class 12 Notes: CBSE Chemistry Chapter 1

Electrochemistry Class 12 Notes: CBSE Chemistry Chapter 2
