The van's Hoff factor i for a compound which undergoes dissociation in one solvent and association in other solvent is respectively:
Less than one and greater than one
Less than one and less than one.
Greater than one and less than one.
Greater than one and greater than one.
As learnt
Vant Hoff factor for dissociation -
number of particles associated
degree of association
e.g. Carboxylic acid dimerized in non polar solvents like Hexane.
- wherein
n = 2 for dimerization
n = 3 for trimerization
AND
Vant Hoff factor for dissociation -
Where
is the no. of dissociated particles
degree of association
- wherein
Van't Hoff factor for association, ,where n=2 for dimerization
n=3 for trimerization
< 1
and Van't Hoff factor for dissociation, where n=2, 3 ....... (no. of dissociated particles)
> 1
Therefore, i <1 for association
and, i > 1 for dissociation
Option 1)
Less than one and greater than one
This option is incorrect
Option 2)
Less than one and less than one.
This option is incorrect
Option 3)
Greater than one and less than one.
This option is correct
Option 4)
Greater than one and greater than one.
This option is incorrect