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 |
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 |
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 |
During osmosis, the flow of water through a semi-permeable membrane is:
1. | From a solution having higher concentration only. |
2. | From both sides of the semi-permeable membrane with equal flow rates. |
3. | From both sides of the semi-permeable membrane with unequal flow rates. |
4. | From a solution having lower concentration only. |
A solution of acetone in ethanol:
1. | Shows a negative deviation from Raoult's law |
2. | Shows a positive deviation from Raoult's law |
3. | Behaves like a near-ideal solution |
4. | Obeys Raoult's law |
1.00 g of non-electrolyte solute (molar mass 250 g mol-1) was dissolved in 51.2 g of benzene. If the freezing point depression constant, Kf of benzene is 5.12 mol-1 kg K, the freezing point of benzene will be lowered by:
1. 0.4 K
2. 0.3 K
3. 0.5 K
4. 0.2 K
A solution containing 10 g/dm3 of urea (molecular mass = 60 g mol-1) is isotonic with a 5 % solution of a non-volatile solute. The molecular mass of this non-volatile solute is:
1. | 25 g mol-1 | 2. | 300 g mol-1 |
3. | 350 g mol-1 | 4. | 200 g mol-1 |
0.5 molal aqueous solution of a weak acid (HX) is 20 % ionised. The lowering in the freezing point of the solution will be:
[Kf for water = 1.86 K kg mol-1]
1. -1.12 K
2. 0.56 K
3. 1.12 K
4. -0.56 K
A 0.0020 m aqueous solution of an ionic compound Co(NH3)5(NO2)Cl freezes at -0.0073 oC. The number of moles of ions that 1 mol of ionic compound produces on being dissolved in water will be:
(Kf = -1.86 oC/m)
1. | 2 | 2. | 3 |
3. | 4 | 4. | 1 |