Advertisements
Advertisements
Question
In the plot of molar conductivity (∧m) vs square root of concentration (c1/2) following curves are obtained for two electrolytes A and B : 
Answer the following:
(i) predict the nature of electrolytes A and B.
(ii) What happens on the extrapolation of ∧m to concentration approaching for electrolytes A and B?
Advertisements
Solution
Electrolyte A is strong electrolyte & Electrolyte B is weak electrolyte On extrapolation of Λm to concentration approaching zero for strong electrolytes, we get the value of Λ=m i.e. molar conductance at infinite dilution In the case of weak electrolytes, Λm increases steeply on dilution. Therefore, Λ=m cannot be obtained by extrapolation.
APPEARS IN
RELATED QUESTIONS
The conductivity of 0.20 M solution of KCl at 298 K is 0.025 S cm−1. Calculate its molar conductivity.
Define limiting molar conductivity.
The conductivity of sodium chloride at 298 K has been determined at different concentrations and the results are given below:
| Concentration/M | 0.001 | 0.010 | 0.020 | 0.050 | 0.100 |
| 102 × κ/S m−1 | 1.237 | 11.85 | 23.15 | 55.53 | 106.74 |
Calculate ∧m for all concentrations and draw a plot between ∧m and c1/2. Find the value of `∧_m^0`.
Write mathematical expression of molar conductivity of the given solution at infinite dilution.
Solutions of two electrolytes ‘A’ and ‘B’ are diluted. The Λm of ‘B’ increases 1.5 times while that of A increases 25 times. Which of the two is a strong electrolyte? Justify your answer. Graphically show the behavior of ‘A’ and ‘B’.
The molar conductance of NaCl, HCl, and CH3COONa at infinite dilution are 126.45, 426.16, and 91.0 S cm2 mol−1 respectively. The molar conductance of CH3COOH at infinite dilution is. Choose the right option for your answer.
The variation of molar conductivity with concentration of an electrolyte (X) m aqueous solution is shown in the given figure.

The electrolyte X is ______.
Assertion (A) : Conductivity decreases with decrease in concentration of electrolyte.
Reason (R) : Number of ions per unit volume that carry the current in a solution decreases on dilution.
Assertion (A): Molar conductivity decreases with increase in concentration.
Reason (R): When concentration approaches zero, the molar conductivity is known as limiting molar conductivity.
Which of the following solutions will have the highest conductivity at 298 K?
