The boiling point of an azeotropic mixture of water and ethanol is less than that of water and ethanol individually. The mixture shows:
1. No deviation from Raoult's law
2. Positive deviation from Raoult's law
3. Negative deviation from Raoult's law
4. That the solution is unsaturated
A pair of isotonic solutions, among the following, is (assuming temperature to be the same) :
1. 0.1 (M) urea and 0.1 (M) NaCl
2. 0.1 (M) urea and 0.2 (M) MgCl2
3. 0.1 (M) NaCl and 0.1 (M) Na2SO4
4. 0.1 (M) Ca(NO3)2 and 0.1 (M) Na2SO4
The correct statement regarding a solution of two components A and B exhibiting positive deviation from ideal behaviour is :
1. | Intermolecular attractive force between A-A and B-B are stronger than those between A-B |
2. | ∆mixH = 0 at constant T and P |
3. | ∆mixV = 0 at constant T and P |
4. | Intermolecular attractive forces between A-A and B-B are equal to those between A-B |
A 500 g toothpaste sample has 0.4 g fluoride concentration. The fluoride concentration in terms of ppm will be -
1. | 200 ppm | 2. | 400 ppm |
3. | 500 ppm | 4. | 800 ppm |
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:
(rounded off up to two decimal places)
1. 0.80 K
2. 0.40 K
3. 0.60 K
4. 0.20 K
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
Preservation of fruits against bacterial action by adding sugar is an example of-
1. Exosmosis
2. Reverse-osmosis
3. Diffusion
4. Capillary action
The mixture among the following that forms maximum boiling azeotrope is:
1. | Heptane + Octane | 2. | Water + Nitric acid |
3. | Ethanol + Water | 4. | Acetone + Carbon disulphide |
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 |