ABSTRACT
Conductivity is a physical quantity we can measure with high precision and good reproducibility. In the conductometric studies of ionic solutions, the two conductivities have been traditionally employed: specific conductivity (k) and equivalent
conductivity () or molar conductivity defined as a quotient of k divided by concentration (C). In the area of colloid science of ionic surfactant solution, these conductivities have been extensively used mainly for determining the critical micelle concentration (CMC) of ionic surfactant, at which the concentration dependence of each conductivity breaks.
