Question

Consider the manufacturing of Linear Alkyl Benzene Sulphonates (LABS). The alkylbenzenes are sulphonated with:

• A. 50% sulphuric acid
• B. 98% sulphuric acid
• C. 20% oleum
• D. sulphur trioxide gas

Hint:

Sulphonation of alkylbenzenes in LABS production is carried out with concentrated 98% sulphuric acid to ensure an efficient reaction.

Answer 1

The Correct Option is B

Step 1: Understanding the sulphonation process.
In the manufacturing of LABS, sulphonation is typically carried out using concentrated sulphuric acid (98%), which is a strong acid required for the reaction.

Step 2: Explanation of options.
- (B) 98% sulphuric acid is the correct reagent for sulphonation in LABS production. - (A) 50% sulphuric acid is not concentrated enough for this process. - (C) 20% oleum is too dilute for sulphonation. - (D) Sulphur trioxide gas is used in some processes but not typically for this sulphonation.

Final Answer: \[ \boxed{\text{B) 98% sulphuric acid}} \]