Solutions

What is the freezing point depression constant of a solvent, 50 g of which contain 1 g non-volatile solute (molar mass 256 g mol-1) and the decrease in freezing point is 0.40 K?

1. 4.43 K kg mol-1
2. 3.72 K kg mol-1
3. 5.12 K kg mol-1
4. 1.86 K kg mol-1

Assume a living cell with 0.9% (w/w) of glucose solution (aqueous). This cell is immersed in another solution having equal mole fraction of glucose and water. (Consider the data upto first decimal place only) The cell will :

1. shrink since solution is 0.45% (w/w) as a result of association of glucose molecules (due to hydrogen bonding)
2. shrink since solution is 0.5% (w/w)
3. show no change in volume since solution is 0.9% (w/w)
4. swell up since solution is 1% (w/w)

Consider the given plots of vapour pressure (VP) vs temperature (T/K). Which amongst the following options is correct graphical representation showing Tf, depression in the freezing point of a solvent in a solution?

1. [figure]
2. [figure]
3. [figure]
4. [figure]

The observed and normal molar masses of compound MX2 are 65.6 and 164 respectively. The percent degree of ionisation of MX2 is %. (Nearest integer)

CrCl3 xNH3 can exist as a complex. 0.1 molal aqueous solution of this complex shows a depression in freezing point of 0.558 C. Assuming 100% ionisation of this complex and coordination number of Cr is 6, the complex will be (Given Kf = 1.86 K kg mol-1)

1. [Cr(NH3)5Cl]Cl2
2. [Cr(NH3)4Cl2]Cl
3. [Cr(NH3)6]Cl3
4. [Cr(NH3)3Cl3]

When a non-volatile solute is added to the solvent, the vapour pressure of the solvent decreases by 10 mm of Hg. The mole fraction of the solute in the solution is 0.2. What would be the mole fraction of the solvent if decrease in vapour pressure is 20 mm of Hg ?

1. 0.2
2. 0.4
3. 0.8
4. 0.6

Consider a binary solution of two volatile liquid components 1 and 2. x1 and y1 are the mole fractions of component 1 in liquid and vapour phase, respectively. The slope and intercept of the linear plot of 1x1 vs 1y1 are given respectively as :

1. P10P20, P10-P20P20
2. P20P10, P20-P10P10
3. P20P10, P10-P20P20
4. P10P20, P20-P10P20

Arrange the following solutions in order of their increasing boiling points. (i) 10-4 M NaCl (ii) 10-4 M Urea (iii) 10-3 M NaCl (iv) 10-2 M NaCl

1. (i) < (ii) < (iii) < (iv)
2. (ii) < (i) < (iii) < (iv)
3. (iv) < (iii) < (i) < (ii)
4. (ii) < (i) (iii) < (iv)

Density of 3 M NaCl solution is 1.25 g/mL. The molality of the solution is :

1. 2.79 m
2. 2 m
3. 1.79 m
4. 3 m