COMEDK 2024 Shift 2 Paper

For addressing the given statements, let's analyze both the Assertion and the Reason carefully.
Assertion: When Molar conductivity for a strong electrolyte is plotted versus √C(mol∕L)1∕2, a straight line is obtained with intercept equal to Molar conductivity at infinite dilution for the electrolyte and Slope equal to - A. All electrolytes of a given type have the same A value.
This assertion stems from Kohlrausch's Law of Independent Migration of lons. For strong electrolytes, the molar conductivity at a given concentration C is generally expressed as:
Λm=Λm∞−A√C
where Λm is the molar conductivity at concentration C,Λm∞ is the molar conductivity at infinite dilution, and A is a constant dependent on the nature of the electrolyte and the temperature.
When plotted, Λm vs √C indeed yields a straight line with intercept Λm∞ and slope −A. The value of A is typically the same within electrolyte types under identical conditions, making the assertion correct.
Reason: At infinite dilution, strong electrolytes of the same type will have different number of ions due to incomplete dissociation.
This reason contradicts the general understanding of strong electrolytes. At infinite dilution, strong electrolytes are assumed to dissociate completely into their respective ions. Thus, strong electrolytes of the same type are expected to have the same number of ions at infinite dilution, making the reason incorrect.
Given this analysis, the correct option is:
Option A
Assertion is correct but Reason is incorrect statement.