The boiling point of 0.2 mol kg-1 solution of X in water is greater than equimolal solution
of Y in water. Which one of the following statements is true in this case?
1. X is undergoing dissociation in water
2. Molecular mass of X is greater than the molecular mass of Y
3. Molecular mass of X is less than the molecular mass of Y
4. Y is undergoing dissociation in water while X undergoes no change
Which one of the following elctrolytes has the same value of van't Hoff's factor(i) as
that of Al2(SO4)3 (if all are 100% ionised)?
1. K2SO4
2. K3[Fe(CN)6]
3. Al(NO3)3
4. K4[Fe(CN)6]
Of the following 0.10 m aqueous solutions, which one will exhibit the largest freezing
point depression?
1. KCl
2. C6H12O6
3. Al2(SO4)3
4. K2SO4
pA and pB are the vapour pressure of pure liquid components, A and B, respectively of an
ideal binary solution.If x, represents the mole fraction of component A, the total pressure
of the solution will be.
1. pA + xA(pB-pA)
2. pA + xA(pA-pB)
3. pB + xA(pB-pA)
4. pB + xA(pA-pB)
Limiting molar conductivity of NH4OH (i.e Åm(NH4OH)) is equal to:-
1. Åm (NH4Cl)+Åm(NaCl)-Åm(NaOH)
2. Åm(NaOH)+Åm(NaCl)-Åm(NH4Cl)
3. Åm(NH4OH)+Åm(NH4Cl)-Åm(HCl)
4. Å(NH4Cl)+Å(NaOH)-Å(NaCl)
The freezing point depression constant format is -1.86°C m-1. If 5.00g Na2SO4 dissolved
in 45.0 g H2O, the freezing point is changed by -3.82°C. Calculate the van't Hoff factor
for NaSO4
1. 2.63
2. 3.11
3. 0.381
4. 2.05
The van't Hoff factor, i for a compound which undergoes dissociation in one solvent and
association in other solvent is respectively.
1. less than one and less than one
2. greater than one and less than one
3. greater than one and greater than one
4. less than one and greater than one
An aqueous solution is 1.00 molal in KI. Which change will cause the vapour pressure of
the solution to increase ?
1. Addition of NaCl
2. Addition of Na2SO4
3. Addition of 1.00 molal KI
4. Addition of water
A solution of sucrose (molar mass = 342 g mol-1) has been prepared by dissolving 68.5 g of sucrose in 1000 g of water.
The freezing point of the solution obtained will be:
(Kf for water = 1.86 K kg mol-1)
1. -0.372 C
2. 0.372 C
3. 0.572 C
4. -0.572 C
An increase in equivalent conductance of a strong electrolyte with dilution is mainly due
to
1. increase in ionic mobility of ions
2. 100% ionisation of electrolyte at normal dilution
3. increase in both, i.e. number of ions and ionic mobility of ions
4. increase in number of ions