Question

CMC value of soaps is?

Answer 1

The variation of detergent anion activity with, concentration in solutions of potassium laurate, myristate, palmitate and stearate has been studied using the cobalt, cobalt soap electrode. The detergent anion activity increases at first, reaches a maximum at the c.m.c. and thereafter remains almost constant. The constant value of the activity above the c.m.c. shows that the excess of soap added goes into solution in the form of micelles. The c.m.c. values of potassium laurate, myristate, palmitate and stearate are 2.512 × 10−2M, 6.918 × 10−3M ,3.162 × 10−3M and 8.71 × 10−4M, respectively. In the presence of urea, the rnicellization of potassium laurate and myristate takes place at higher concentrations.

Answer 2

Answer:

The constant value of the activity above the c.m.c. shows that the excess of soap added goes into solution in the form of micelles. The c.m.c. values of potassium laurate, myristate, palmitate and stearate are 2.512 × 10−2 M, 6.918 × 10−3M ,3.162 × 10−3 M and 8.71 × 10−4M, respectively.