The amount of benzoic acid (C6H5COOH) required for preparing 250 mL of 0.15 M solution in methanol is:
| 1. | 4.57 g | 2. | 3.57 g |
| 3. | 1.57 g | 4. | 12.57 g |
The depression in the freezing point of water was observed for the same amount of acetic acid, trichloroacetic acid, and trifluoroacetic in the order of-
1. acetic acid < trichloroacetic acid < trifluoroacetic acid
2. acetic acid > trichloroacetic acid > trifluoroacetic acid
3. acetic acid < trichloroacetic acid > trifluoroacetic acid
4. acetic acid > trichloroacetic acid < trifluoroacetic acid
The depression in the freezing point of water when 10 g of CH3CH2CHClCOOH is added to 250 g of water will be:
(Ka = 1.4 × 10–3, Kf = 1.86 K kg mol–1)
1. 0.32 K
2. 2.87 K
3. 0.65 K
4. 5.03 K
When 19.5 g of fluoroacetic acid (CH2FCOOH) is dissolved in 500 g of water, the observed depression in the freezing point was found to be 1.00 K. The Van’t Hoff factor and the dissociation constant of the fluoroacetic acid, respectively are: (Given: \(K_f\) for water = 1.86 K kg mol⁻¹, Molar mass of CH2FCOOH = 78 g mol⁻¹)
| 1. | 20.75 , 4.77 × 10–3 | 2. | 1.075 , 4.77 × 10–2 |
| 3. | 2.073 , 3.07 × 10–4 | 4. | 1.075 , 3.07 × 10–3 |
100 g of liquid A (molar mass 140 g mol–1) was dissolved in 1000 g of liquid B (molar mass 180 g mol–1). The vapour pressure of pure liquid B was found to be 500 torr. If the total vapour pressure of the solution is 475 torr, the vapour pressure of pure liquid A will be:
| 1. | 326 torr | 2. | 226 torr |
| 3. | 360.7 torr | 4. | 280.7 torr |
Air consists primarily of nitrogen, which occupies approximately 79% by volume at 298 K under normal conditions. Water is in equilibrium with air at a total pressure of 10 atm and a temperature 298 K. The Henry's law constant for nitrogen in water at 298 K is given as 6.51 × 10⁷ mm Hg.
Determine the mole fraction of dissolved nitrogen in the water under these conditions:
| 1. | 12.4 × 10−5
|
2. | 9.22 × 10−5
|
| 3. | 3.54 × 10
|
4. | 4.96 × |
The amount of CaCl2 (i = 2.47) dissolved in 2.5 litre of water such that its osmotic pressure is 0.75 atm at 27 °C is:
| 1. | 1.02 g | 2. | 4.35 g |
| 3. | 2.87 g | 4. | 3.42 g |
If 22 g of benzene is dissolved in 122 g of CCl4, the mass percentage of CCl4 and benzene respectively are-
1.
2.
3.
4. 91.28 %, 8.72 %
Match the following type of intermolecular interactions present in the pair of compounds given:
| (a) | Methanol and Acetone | (i) | Van der Waal’s forces of attraction |
| (b) | Acetonitrile and Acetone | (ii) | Ion-dipole interaction |
| (iii) | Dipole-dipole interaction |
| (a) | (b) | |
| 1. | (iii) | (ii) |
| 2. | (ii) | (ii) |
| 3. | (iii) | (iii) |
| 4. | (iii) | (i) |
What is the mole fraction of benzene in a solution where benzene constitutes 30% by mass in carbon tetrachloride (\(\text{CCl}_4\))?
1. 0.46
2. 0.64
3. 0.91
4. 0.19