Question

Which of the following is a cationic detergent?

• A. n-hexadecyl trimethyl ammonium chloride
• B. Pentaerythrityl stearate
• C. n-dodecyl benzene sulphonic acid
• D. Sodium lauryl sulphate

Hint:

Cationic detergents have a positively charged hydrophilic group and are used in fabric softeners and conditioners, such as n-hexadecyl trimethyl ammonium chloride.

Answer 1

The Correct Option is A

Step 1: Understanding cationic detergents.
Cationic detergents are surfactants that carry a positive charge on their hydrophilic head. These detergents are used in fabric softeners, hair conditioners, and other applications due to their ability to interact with negatively charged surfaces.
Step 2: Analyzing the options.
(A) n-hexadecyl trimethyl ammonium chloride: This is a cationic detergent. It contains a positively charged ammonium group, which gives it its cationic properties.
(B) Pentaerythrityl stearate: This is an ester and not a detergent.
(C) n-dodecyl benzene sulphonic acid: This is an anionic detergent, not cationic.
(D) Sodium lauryl sulphate: This is also an anionic detergent, not cationic.
Step 3: Conclusion.
The correct answer is (A) n-hexadecyl trimethyl ammonium chloride.