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Question
Why on dilution the m Λm of \[\ce{CH3COOH}\] increases very fast, while that of \[\ce{CH3COONa}\] increases gradually?
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Solution
In the case of \[\ce{CH3COOH}\], which is a weak electrolyte, the number of ions increase on dilution due to an increase in degree of dissociation.
\[\ce{CH3COOH + H2O ⇌ CH3COO^{-} (aq) + H3O^{+}}\]
In the case of strong electrolyte such as \[\ce{CH3COONa}\], the number of ions remains the same but the interionic attraction decreases.
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| Column I | Column II |
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\[\begin{array}{cc}
\end{array}\]\[\begin{bmatrix}
\ce{\Lambda^{\circ}_{H^+} = 350 S cm^2 mol^{-1}}\\
\ce{\Lambda^{\circ}_{CH_3COO^-} = 50 S cm^2 mol^{-1}}
\end{bmatrix}\]
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