CBSE Class 12-science Answered

Kohlrausch law states that, “At time infinite dilution, the molar conductivity of an electrolyte can be expressed as the sum of the contributions from its individual ions” i.e. ?^?_m = v₊ ?^?₊ + v_- ?^?_-, where, v₊ and V_- are the number of cations and anions per formula unit of electrolyte respectively and, ?^?₊ and ?^?_- are the molar conductivities of the cation and anion at infinite dilution respectively. The use of above equation in expressing the molar conductivity of an electrolyte is illustrated as,

The molar conductivity of HCl at infinite dilution can be expressed as,

?^?_HCI = V_H+?^?_H + V_CI-?^?_CI-; For HCI, V_H+ = 1 and V_CI- = 1. So, ?^?_HCI = (1 x ?^?_H+) + (1 x ?^?_H-); Hence,

?^?_HCI = ?^?_H+ + ?^?_CI-