Camphor is often used in molecular mass determination because:
1. It has a very high cryoscopic constant
2. It is volatile
3. It is a solvent for organic substances
4. It is readily available
From the colligative properties of a solution, which one is the best method for the determination of molecular weight of proteins & polymers:
1. Osmotic pressure
2. Lowering of vapour pressure
3. Lowering of freezing point
4. Elevation in boiling point
A solution contains a non-volatile solute of molecular mass M2. The molecular mass of solute in terms of osmotic pressure is:
where:
m2 → Mass of solute
V → Volume of solution
\(\pi\) → Osmotic pressure
1.
2.
3.
4.
The ideal solution indicates:
1. | A – B attraction force is greater than A – A and B – B. |
2. | A – B attraction force is less than A – A and B – B. |
3. | Attraction force remains the same in A – A and B – B. |
4. | The volume of the solution is different from the sum of the volume of the solute and solvent. |
Beans get cooked earlier in a pressure cooker, because:
1. | The boiling point increases with increasing pressure |
2. | The boiling point decreases with increasing pressure |
3. | The extra pressure of the pressure cooker softens the beans |
4. | Internal energy is not lost while cooking in a pressure cooker |
If 22 g of benzene is dissolved in 122 g of carbon tetrachloride then the mass percentage of carbon tetrachloride (CCl4) is-
1. 82.72%
2. 83.72%
3. 84.72%
4. 85.72%
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. 0.66 bar
2. 0.96 bar
3. 0.76 bar
4. 0.19 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
The vapour pressure of 1 molal solution of a non-volatile solute in water at 300 K would be -
(The vapour pressure of water at 300 K = 12.3 kPa)
1. | 21.08 kPa | 2. | 12.08 kPa |
3. | 33.08 kPa | 4. | 4.08 kPa |
A solution containing 30 g of non-volatile solute in 90 g of water has a vapour pressure of 2.8 kPa at 298 K. Further, 18 g of water is then added to the solution and the new vapour pressure becomes 2.9 kPa at 298 K.
The molar mass of the solute will be -
1. 23 g mol−1
2. 34 g mol−1
3. 15 g mol−1
4. 46 g mol−1