A : Micelles can be formed at above CMC and at below Kraft temperature.
R : For NaCl solution, Kraft temperature is `60^(@)` C .

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, mark (1)
B. If both Assertion & Reason are true but reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Resson are false statements , then mark (4)

Answer

To analyze the statements given in the question, we will evaluate the assertion (A) and the reason (R) separately.

### Step 1: Understanding Micelles and CMC
Micelles are aggregates of surfactant molecules that form in a solution when the concentration of the surfactant exceeds a certain threshold known as the Critical Micelle Concentration (CMC). Below this concentration, surfactant molecules exist as individual entities, while above this concentration, they start to form micelles, which have a hydrophilic (water-attracting) head and a hydrophobic (water-repelling) tail.

**Hint:** Recall the definition of CMC and the structure of surfactants to understand micelle formation.

### Step 2: Evaluating Assertion (A)
The assertion states that micelles can be formed above CMC and below Kraft temperature. The Kraft temperature is the temperature above which micelles can form in a surfactant solution. Therefore, the assertion is correct because micelles can indeed form when the concentration is above CMC, as long as the temperature is below the Kraft temperature.

**Hint:** Think about the conditions required for micelle formation and the role of temperature.

### Step 3: Evaluating Reason (R)
The reason states that for a NaCl solution, the Kraft temperature is 60°C. However, NaCl is an ionic compound and does not behave like a surfactant. Micelles are typically formed by surfactants that have both hydrophilic and hydrophobic parts. In the case of NaCl, it does not have the necessary structure to form micelles, and thus the concept of Kraft temperature does not apply in the same way as it does for surfactants.

**Hint:** Consider the nature of NaCl and its ability to form micelles compared to surfactants.

### Step 4: Conclusion
Since the assertion is true, but the reason provided is false (as NaCl does not form micelles), we conclude that:

- Assertion (A) is true.
- Reason (R) is false.

### Final Answer:
The assertion (A) is true, and the reason (R) is false.