Preservation of fruits against bacterial action by adding sugar is an example of-
1. Exosmosis
2. Reverse-osmosis
3. Diffusion
4. Capillary action
Colligative properties are dependent on which of the following factors?
| 1. | The nature of the solute particles dissolved in the solution. |
| 2. | The number of solute particles in the solution. |
| 3. | The physical properties of the solute particles dissolved in the solution. |
| 4. | The nature of solvent particles. |
A solution that has the highest boiling point among the following is:
1. 1.0 M NaOH
2. 1.0 M Na2SO4
3. 1.0 M NH4NO3
4. 1.0 M KNO3
The unit of Ebullioscopic constant is:
1. K kg mol–1 or K (molality)–1
2. mol kg K–1 or K–1 (molality)
3. kg mol–1 K–1 or K–1 (molality)–1
4. K mol kg–1 or K (molality)
In comparison to a 0.01 M solution of glucose, the depression in the freezing point of a 0.01 M MgCl2 solution will be:
| 1. | Same | 2. | About twice |
| 3. | About three times | 4. | About six times |
Match the laws/colligative properties given in Column-I with expressions given in Column-II.
| Column-I | Column-II | ||
| A. | Raoult’s law | I. | \(\mathrm{\pi=C R T}\) |
| B. | Osmotic pressure | II. | \(\Delta \mathrm{T}_{\mathrm{f}}=\mathrm{K}_{\mathrm{f}} \mathrm{~m}\) |
| C. | Elevation of boiling point | III. | \(\mathrm{p=x_1 p_1^0+x_2 p_2^0}\) |
| D. | Depression in freezing point | IV. | \(\Delta \mathrm{T}_{\mathrm{b}}=\mathrm{K}_{\mathrm{b}} \mathrm{~m}\) |
Codes:
| A | B | C | D | |
| 1. | I | III | IV | I |
| 2. | I | II | III | IV |
| 3. | I | IV | III | II |
| 4. | III | I | IV | II |
The azeotropic mixture of water and ethanol boils at 78.15 oC. When this mixture is distilled, it is possible to obtain-
1. Pure H2O
2. Pure C2H5OH
3. Pure H2O as well as pure C2HOH
4. Neither H2O nor C2H5OH in their pure state
The freezing point of depression constant (Kf ) of benzene is 5.12 K kg mol–1. The freezing point depression for the solution of molality 0.078 m containing a non-electrolyte solute in benzene is:
1. 0.80 K
2. 0.40 K
3. 0.60 K
4. 0.20 K
The partial pressure of ethane over a solution containing 6.56 × 10–2 g of ethane is 1 bar. If the solution contains 5.00 × 10–2 g of ethane, the partial pressure of the gas will be:
1. 0.76 bar
2. 0.16 bar
3. 1.16 bar
4. 3.16 bar
The positive deviations from Raoult’s law mean the vapour pressure is:
1. Higher than expected.
2. Lower than expected.
3. As expected.
4. None of the above