An example of micelle is

Options

A. `As_(2)O_(3)` sol.
B. Ruby glass
C. `Na_(2)CO_(3)` solution
D. Sodium stearate concentrated solution

Answer

To solve the question "An example of micelle is," we need to understand what a micelle is and identify the correct option from the given choices.

### Step-by-Step Solution:

1. **Understanding Micelles**:
- Micelles are aggregates of surfactant molecules that form in a solution. They consist of a hydrophilic (water-attracting) "head" and a hydrophobic (water-repelling) "tail."
- In aqueous solutions, these molecules arrange themselves in a spherical shape where the hydrophilic heads face outward toward the water, and the hydrophobic tails are tucked away from the water.

2. **Analyzing the Options**:
- **Option A: A2SO3 (Arsenic Trioxide)**: This is a metal oxide and does not have the structure of a micelle as it does not contain both hydrophilic and hydrophobic parts.
- **Option B: Ruby Glass**: Known as gold ruby, this is a type of glass made with gold salts. It does not possess the characteristics of a micelle.
- **Option C: Sodium Carbonate**: This is an inorganic salt that dissolves in water but does not form micelles since it does not have the necessary structure.
- **Option D: Sodium Stearate**: This compound (C18H35NaO2) has a long hydrophobic hydrocarbon chain and a hydrophilic sodium carboxylate head. This structure allows it to form micelles in aqueous solutions.

3. **Conclusion**:
- The only option that fits the definition of a micelle is **Option D: Sodium Stearate**.

### Final Answer:
**An example of micelle is Sodium Stearate.**

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