1. What is Micellar Aggregation Number?

Definition: The Micellar Aggregation Number is defined as the number of surfactant molecules required to form the micelles.

Purpose: It helps in understanding the size and structure of micelles formed by surfactant molecules in solution.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( N_{mic} \) — Micellar Aggregation Number
• \( R_{mic} \) — Micelle Core Radius (Å)
• \( V_{hydrophobic} \) — Volume of Hydrophobic Tail (m³)
• \( \pi \) — Archimedes' constant (~3.1416)

Explanation: The formula calculates how many surfactant molecules can fit into a micelle based on the micelle's core volume and the volume occupied by each hydrophobic tail.

3. Importance of Micellar Aggregation Number

Details: This number is crucial for understanding surfactant behavior, designing detergents, and studying biological membrane systems.

4. Using the Calculator

Tips: Enter the micelle core radius in angstroms (Å) and the hydrophobic tail volume in cubic meters (m³). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical micelle core radius?
A: For common surfactants, the radius typically ranges from 10-50 Å, depending on the surfactant type and conditions.

Q2: How do I determine the hydrophobic tail volume?
A: It can be estimated using molecular modeling or from known values for specific hydrocarbon chains.

Q3: What affects the micellar aggregation number?
A: Temperature, surfactant concentration, and the presence of electrolytes can all influence this number.

Q4: What's a typical range for aggregation numbers?
A: Most surfactants form micelles with aggregation numbers between 20-100 molecules.

Q5: Can this calculator be used for reverse micelles?
A: The same principles apply, but the volume would be for the hydrophilic head groups instead.