Kohlrausch's Law of Independent Migration of Ions
Kohlrausch's Law of Independent Migration of Ions states that at infinite dilution, each ion
contributes independently to the total molar conductivity of an electrolyte, regardless of the
presence of other ions.
This law is important in electrochemistry for calculating the limiting molar conductivity of
electrolytes and understanding ion transport in solutions.
Mathematical Expression:
According to Kohlrausch's Law:
lambda_m^(infinity) = lambda^(infinity)(cation) + lambda^(infinity)(anion)
Where:
lambda_m^(infinity) = Limiting molar conductivity of the electrolyte
lambda^(infinity)(cation) = Contribution of the cation at infinite dilution
lambda^(infinity)(anion) = Contribution of the anion at infinite dilution
Applications of Kohlrausch's Law:
1. Determining the molar conductivity of weak electrolytes.
2. Calculation of ion transport numbers.
3. Determining the degree of ion dissociation (α) of weak electrolytes.
4. Estimating solubility of sparingly soluble salts.
Conclusion:
Kohlrausch's Law plays a crucial role in electrochemistry by explaining how ions contribute to
conductivity independently at infinite dilution. It helps in understanding the behavior of
electrolytes and their dissociation properties.
Kohlrausch's Law of Independent Migration of Ions states that at infinite dilution, each ion
contributes independently to the total molar conductivity of an electrolyte, regardless of the
presence of other ions.
This law is important in electrochemistry for calculating the limiting molar conductivity of
electrolytes and understanding ion transport in solutions.
Mathematical Expression:
According to Kohlrausch's Law:
lambda_m^(infinity) = lambda^(infinity)(cation) + lambda^(infinity)(anion)
Where:
lambda_m^(infinity) = Limiting molar conductivity of the electrolyte
lambda^(infinity)(cation) = Contribution of the cation at infinite dilution
lambda^(infinity)(anion) = Contribution of the anion at infinite dilution
Applications of Kohlrausch's Law:
1. Determining the molar conductivity of weak electrolytes.
2. Calculation of ion transport numbers.
3. Determining the degree of ion dissociation (α) of weak electrolytes.
4. Estimating solubility of sparingly soluble salts.
Conclusion:
Kohlrausch's Law plays a crucial role in electrochemistry by explaining how ions contribute to
conductivity independently at infinite dilution. It helps in understanding the behavior of
electrolytes and their dissociation properties.
