Which of the following are anionic detergents?
I. Sodium salts of sulphonated long chain alcohol.
II. Ester of stearic acid and polyethylene glycol.
III. Quaternary ammonium salt of amine with acetate ion.
IV. Sodium salts of sulphonated long chain hydrocarbons.
The correct option is

Options

A. I and II
B. II and III
C. I and IV
D. II and IV

Answer

To determine which of the given options are anionic detergents, let's analyze each option step by step.

### Step 1: Understanding Anionic Detergents
Anionic detergents are characterized by the presence of a negatively charged ion (anion) in their structure. They are typically sodium salts of sulfonated long-chain alcohols or hydrocarbons.

### Step 2: Analyzing Each Option
1. **Option I: Sodium salts of sulphonated long chain alcohol**
- This option fits the definition of anionic detergents because it is a sodium salt and contains a sulfonate group, which is negatively charged.
- **Conclusion**: This is an anionic detergent.

2. **Option II: Ester of stearic acid and polyethylene glycol**
- Esters are generally non-ionic in nature. This option does not contain a negatively charged ion and does not fit the definition of anionic detergents.
- **Conclusion**: This is not an anionic detergent.

3. **Option III: Quaternary ammonium salt of amine with acetate ion**
- Quaternary ammonium salts are typically cationic detergents, not anionic. The presence of acetate ion does not change its classification as cationic.
- **Conclusion**: This is not an anionic detergent.

4. **Option IV: Sodium salts of sulphonated long chain hydrocarbons**
- Similar to option I, this option also represents anionic detergents as they are sodium salts of sulfonated hydrocarbons, which contain a negatively charged sulfonate group.
- **Conclusion**: This is an anionic detergent.

### Step 3: Final Conclusion
Based on the analysis:
- **Anionic Detergents**: I and IV
- **Not Anionic Detergents**: II and III

### Correct Options
The correct options that are anionic detergents are **I and IV**.