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Question
Assertion (A): Molar conductivity decreases with increase in concentration.
Reason (R): When concentration approaches zero, the molar conductivity is known as limiting molar conductivity.
Options
Both (A) and (R) are true and (R) is the correct explanation of (A).
Both (A) and (R) are true, but (R) is not the correct explanation of (A).
(A) is true, but (R) is false.
(A) is false, but (R) is true.
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Solution
Both (A) and (R) are true, but (R) is not the correct explanation of (A).
Explanation:
Molar conductivity increases as concentration lowers. This is because the total volume, V, of a solution containing one mole of electrolyte increases. A drop in 'κ' following the dilution of a solution has been discovered to be more than countered by an increase in volume. The limiting molar conductivity of a solution is its molar conductivity at infinite dilution. In other words, when the electrolyte concentration approaches zero, the molar conductivity is said to be limiting.
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