1. Assume that the hydrocarbonlike interior cavity of the SDS micelle has a diameter of - 3 nm and that it contains three solubilized benzene molecules. Calculate the "local" concentration of benzene in the micelle

2. Assuming that at 298 K the CMC for a cerrain surfactant is 6 X 10-3 M and that its mean aggregation number is 70, estimate the concentration of micelles if the bulk sur­ factant concentration is 0.08 M.

3. A quantity (390 mg) of n-hexane is solubilized in 100 mL of the surfactant solution in question 2. Assuming that all the solubilized n-hexane molecules are in the micelles, what is the mean occupation number of 71-hexane in the micelles?

4. For the system in question 2, estimate tlGo for micellization if the molecular weight of the surfactant is 326 g mol-I . If the enthalpy of micellization is 8 kJ mol- I, find the en­ tropy change when 1 mol of micelles forms from 70;:mhnomers.

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1 The local concentration of benzene in the micelle can be calculated using the formula for the volume of a sphere V 43r3 where r is the radius of the micelle Since the diameter of the micelle is 3 nm ... View the full answer