Question

What is Kohlrausch law? Write its applications.

Hint:

Kohlrausch's law is particularly useful for calculating the conductivity of electrolytes at infinite dilution.

Answer 1

Step 1: Kohlrausch Law.
Kohlrausch's law states that the molar conductivity of an electrolyte at infinite dilution is the sum of the molar conductivities of its individual ions. Mathematically: \[ \Lambda_m^\infty = \lambda^\infty_+ + \lambda^\infty_- \] where \( \Lambda_m^\infty \) is the molar conductivity at infinite dilution, and \( \lambda^\infty_+ \) and \( \lambda^\infty_- \) are the molar conductivities of the cation and anion respectively. Step 2: Applications.
- It is used to determine the limiting molar conductivity of ions. - It helps in calculating the conductivity of strong and weak electrolytes. - It is also used to calculate the dissociation constant of weak electrolytes.