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प्रश्न
How can you determine limiting molar conductivity, 0 m for strong electrolyte and weak electrolyte?
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उत्तर

For strong electrolyte, plot of m
against c, extrapolated to the y-axis, gives the value of m for
strong electrolyte. For weak electrolyte, intercept is not obtained as o m
cannot be extra apolated to zero conc. hence limiting molar conductivity of weak electrolyte is obtained from that of strong electrolytes. Using Kohlrausch law of independent migration of ions.
`λ_m^0(CH_3COOH) = lamda^0CH_3COONa + lamda_{HCl}^circ - lamda_{NaCl}^circ`
`lamda_m^circ(CH_3COOH) = lamda_{CH_3COO-}^circ + lamda_{H^+}^circ`
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संबंधित प्रश्न
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 `Lambda_m^0`.
Write mathematical expression of molar conductivity of the given solution at infinite dilution.
Define the following terms :
Limiting molar conductivity
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 extrapolation of ∧m to concentration approaching zero for electrolytes A and B?
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 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.
Conductivity of 2 × 10−3 M methanoic acid is 8 × 10−5 S cm−1. Calculate its molar conductivity and degree of dissociation if `∧_"m"^0` for methanoic acid, is 404 S cm2 mol−3.
Which of the following solutions will have the highest conductivity at 298 K?
