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प्रश्न
Define van’t Hoff factor.
उत्तर
The van’t Hoff factor is defined as the ratio of observed colligative property produced by a given concentration of electrolyte solution to the property observed for the same concentration of non-electrolyte solution.
Van't Hoff factor :
To account for the extent of dissociation or association, van’t Hoff introduced a factor i , known as the van’t Hoff factor.
`i = "Observed colligative property of electrolyte solution"/"Observed colligative property of non-electrolyte solution of same concentration"`
It is related to the degree of dissociation as,
`a = "i - 1"/"n’ - 1"`
Value of i :
For association, i < 1
For dissociation, i > 1
No association or dissociation, i = 1
संबंधित प्रश्न
The substance ‘X’, when dissolved in solvent water gave molar mass corresponding to the molecular formula ‘X3’. The van’t Hoff factor (i) is _______.
(A) 3
(B) 0.33
(C) 1.3
(D) 1
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Benzoic acid to Benzaldehyde
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(i) i = `"Normal molar mass"/"Abnormal molar mass"`
(ii) i = `"Abnormal molar mass"/"Normal molar mass"`
(iii) i = `"Observed colligative property"/"Calculated colligative property"`
(iv) i = `"Calculated colligative property"/"Observed colligative property"`
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[Given: R = 0.082 L atm K–1 mol–1]
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[\[\ce{K_{f(H_2O)}}\] = 1.86 K kg mol−1]
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\[\begin{bmatrix}\begin{array}{cc}
\phantom{.......}\ce{CH3}\\
\phantom{....}|\\
\ce{CH3CH2CH2 - \overset{⊕}{N} - CH2CH3}\\
\phantom{....}|\\
\phantom{.......}\ce{CH3}
\end{array}\end{bmatrix}\]\[\ce{OH^- ->[Heat] ?}\]
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