State the following:
Kohlrausch law of independent migration of ions
Kohlrausch law of independent migration of ions
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Solution and Explanation
Kohlrausch's Law of Independent Migration of Ions:
Statement:
Kohlrausch's law of independent migration of ions states that the molar conductivity of an electrolyte at infinite dilution is the sum of the contributions of the individual ions present in the electrolyte. In other words, the conductivity of a solution at infinite dilution is determined by the conductivity of each ion in the solution when it is not affected by the presence of other ions.
Mathematical Form:
The molar conductivity (\(\Lambda_m^\infty\)) at infinite dilution for a strong electrolyte can be expressed as:
\(\Lambda_m^\infty = \lambda_+^\infty + \lambda_-^\infty\)
where: - \(\Lambda_m^\infty\) is the molar conductivity at infinite dilution of the electrolyte. - \(\lambda_+^\infty\) is the limiting molar conductivity of the cation. - \(\lambda_-^\infty\) is the limiting molar conductivity of the anion.
Implication:
According to this law, the contributions of the cation and anion to the total conductivity are independent of each other. This is particularly useful in calculating the conductivity of electrolytes at infinite dilution and in understanding the behavior of ions in a solution.
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\[ NBAI = k\phi \]
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