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 partial pressure of ethane over a saturated solution containing 6.56 X 10-2 g of ethane is 1 bar. If the solution contains 5.00 X 10-2 g of ethane, then what shall be the partial pressure of the gas?
1. 0.76 bar
2. 0.16 bar
3. 1.16 bar
4. 3.12 bar
1. Benzene + Toluene
2. Acetone + Chloroform
3. Chloroethane + Bromoethane
4. Ethanol + Acetone
Considering the formation, breaking and strength of hydrogen bond, predict which of the following mixtures will show a positive deviation from Raoult’s law?
1. Methanol and acetone
2. Chloroform and acetone
3. Nitric acid and water
4. Phenol and aniline
1. | Increases with an increase in temperature. |
2. | Decreases with an increase in temperature. |
3. | Remains constant. |
4. | First increases then decreases. |
Van't Hoff factor (i) is given by the expression:
a.
b.
c.
d.
The correct choice among the given options are:
1. (a, b)
2. (b, c)
3. (c, d)
4. (a, c)
If 8 g of a non-electrolyte solute is dissolved in 114 g of n-octane to reduce its vapor pressure to 80 %, the molar mass (in g mol–1) of the solute is:
[Molar mass of n-octane is 114 g mol–1]
1. | 40 | 2. | 60 |
3. | 80 | 4. | 20 |
200 mL of an aqueous solution contains 1.26 g of protein. The osmotic pressure of this solution at 300 K is found to be 2.57 × 10–3 bar. The molar mass of protein will be:
(R = 0.083 L bar mol–1 K–1):
1. | 61038 g mol–1 | 2. | 51022 g mol–1 |
3. | 122044 g mol–1 | 4. | 31011 g mol–1 |
A solution of urea (molar mass 56 g mol–1) boils at 100.18 ºC at atmospheric pressure. If Kf and Kb for water are 1.86 and 0.512 K kg mol–1 respectively, the above solution will freeze at:
1. –6.54 ºC
2. –0.654 ºC
3. 6.54 ºC
4. 0.654 ºC