Molar conductivity (A) of aqueous solution of sodium stearate, which behaves as a strong electrolyte, is recorded at varying concentrations (C) of sodium stearate. Which one of the following plots provides the correct representation of micelle formation in the solution? (Critical micelle concentration (CMC) is marked with an arrow in the figures)

Options

A.
B.
C.
D.

Answer

C

Explanation

The curve in option (C) represents a typical strong electrolyte curve, where the point of intersection of the two lines gives the critical micelle concentration. According to Kohlrausch.s law,
`wedge_(m)=wedge_(m)^(oo) -bsqrtC`
where `wedge_(m)^(oo)` is the limiting molar conductivity.