The boiling point of 0.2 mol kg–1 solution of X in water is greater than the equimolal solution of Y in water. The correct statement in this case is:
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. |
The electrolyte having the same value of Van't Hoff factor (i) as that of Al2(SO4)3 (if all are 100% ionized) is:
1. K2SO4
2. K3[Fe(CN)6]
3. Al(NO3)3
4. K4[Fe(CN)6]
The largest freezing point depression among the following 0.10 m solutions is shown by:
1. | \(\mathrm{KCl}\) | 2. | \(\mathrm{C_6H_{12}O_6}\) |
3. | \(\mathrm{Al}_2(\mathrm{SO_4})_3\) | 4. | \(\mathrm{K_2SO_4}\) |
pA and pB are the vapour pressure of pure liquid components, A and B, respectively of an ideal binary solution.
If XA 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)
Vapour pressure of chloroform \(\mathrm{(CHCl_3)}\) and dichloromethane \(\mathrm{(CH_2Cl_2)}\) at are 200 mmHg and 41.5 mmHg respectively. Vapour pressure of the solution was obtained by mixing 25.5 g of \(\mathrm{(CHCl_3)}\) and 40 g of \(\mathrm{(CH_2Cl_2)}\) at the same temperature will be: (Molecular mass of \(\mathrm{(CHCl_3)}\) = 119.5 u and molecular mass of \(\mathrm{(CH_2Cl_2)}\) = 85 u)
1. | 90.40 mm Hg | 2. | 119.5 mm Hg |
3. | 75 mm Hg | 4. | 173.9 mm Hg |
The freezing point depression constant for water is 1.86 oC m-1. If 5.00 g Na2SO4 is dissolved in 45.0 g H2O, the freezing point is changed by -3.82 oC. The Van’t Hoff factor for Na2SO4 is:
1. | 2.63 | 2. | 3.11 |
3. | 0.381 | 4. | 2.05 |
The van’t Hoff factor, i, for a compound that undergoes
dissociation and association in a 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.
A 0.1 molal aqueous solution of a weak acid (HA) is 30 % ionized. If Kf for water is 1.86 °C/m, the freezing point of the solution will be:
1. | –0.24 °C | 2. | –0.18 °C |
3. | –0.54 °C | 4. | –0.36 °C |