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प्रश्न
Predict whether van’t Hoff factor, (i) is less than one or greater than one in the following:
CH3COOH dissolved in water
उत्तर
van't hoff factor i = `"total number of moles of particles after dissociation association"/"no.of moles of particls before association dissociation"`
(i) CH3COOH
\[\ce{CH3\underset{1}{C}OOH->[H2O]CH3\underset{1}{C}OO- \underset{+1 = 2}{+H+}\text{(dissociation)} }\]
`i = 2/1 =2 ` (i is greater 1)
(ii) CH3COOH dissolved in benzene
\[\ce {2C\underset{2}{H}3COOH ->[benzene]\underset{1\text{(due to H-bonding)}}{CH3COOH}2}\] (association)
1(due to H-bonding)
`i= 1/2=0.5` (i is less than 1)
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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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(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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