Question

Which of the following statement is correct?
CMC- Critical micelle concentration

• A. Micelle formation becomes appreciable below CMC
• B. Formation of micelles takes place below kraft temperature
• C. Formation of micelles takes place above kraft temperature
• D. None of the above

Answer 1

The correct option is C Formation of micelles takes place above kraft temperature

Colloids are classified into many types based on many aspects.
On basis of the particles of the dispersed phase, colloids are classified into 3 types:
1. Multimolecular colloids
2. Macromolecular colloids
3. Assoicated colloids

Micelles are relatively small, ​spherical structures composed of a few to few thousand molecules that attract one another to ​form larger aggregate which falls in colloidal range.​

Micelles are formed by aggregation of small molecules. Thus, they are also known as associated colloids​.
Eg. Soap in water.

The formation of micelles takes place only above a particular temperature called Kraft temperature $\left(T_k\right)$ and above a particular concentration called critical micelle concentration (CMC).