The molar volume of liquid benzene (density= 0.877 g ml-1) increases by a factor of 2750 as it vapourises at 20°C. At 27°C when a non-volatile solute (that does not dissociate) is dissolved in 54.6cm3 of benzene, vapour pressure of this solution, is found to be 98.88 mm Hg. calculate the freezing point of the solution.

Given: Enthalpy of vapourisation of benzene(l)=394.57 Jg-1. Enthalpy of fusion of benzene (l) = 10.06 kJ mol-1 Molal depression constant for benzene=5.0 K kg mol-1.

1. 177.65 K

2. 277.65 K

3. 517.65 K

4. 237.15 K

Subtopic:  Depression of Freezing Point |
 60%
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints

The depression in the freezing point of water when 10 g of CH3CH2CHClCOOH is added to 250 g of water is -Ka=1.4 X 10-3, Kf=1.86K kg mol-1

1. 0.15°C

2. 2.15°C

3. 1.15°C

4. 0.65°C

Subtopic:  Depression of Freezing Point |
 58%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

The ratio of the vapour pressure of a solution to the vapour pressure of the solvent is

1. Equal to the mole fraction of the solvent

2. Proportional to the mole fraction of the solute

3. Equal to the mole fraction of the solute

4. None of the above

Subtopic:  Relative Lowering of Vapour Pressure |
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

Mole fraction of the component A in vapour phase is X1 and mole fraction of component A in liquid mixture is X2 then 

(PA0 = vapour pressure of pure A; PB0= vapour pressure of pure B),

then total vapour pressure of the liquid mixture is-

1. PA0X2X1

2. PA0X1X2

3. PB0X1X2

4. PB0X2X1

Subtopic:  Relative Lowering of Vapour Pressure |
 59%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

pH of a 0.1 (M) monobasic acid is 2. Osmotic pressure at a given temperature T is-

1. 0.1RT

2. 0.11RT

3. 1.1RT

4. 0.01RT

Subtopic:  Osmosis & Osmotic Pressure |
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

The vapour pressure of pure water at 298K is 23.76mm. The vapour pressure of a solution of sucrose(C12H22O11) in 5.56 moles of water is 23.392mm Hg. The mass of sucrose in the solution is

1. 15 g

2. 45 g

3. 30 g

4. 37.5 g

Subtopic:  Relative Lowering of Vapour Pressure |
 58%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

Among the following options, 0.1 M aqueous solution that will have the lowest freezing point is-

1. Potassium Sulphate. 2. Sodium chloride.
3. Urea. 4. Glucose.

Subtopic:  Depression of Freezing Point |
 68%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
Links
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

The vapour pressure of toluene is 59.1 torr at 313.75 K and 298.7 torr at 353.15 K. Calculate, the molar heat of vaporisation.

1. 37888 J mol-1

2. 27188 J mol-1

3.  12834 J mol-1

4. 571328 J mol-1

Subtopic:  Raoult's Law |
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints

The vapour pressure of a pure liquid solvent A is 0.80 atm. When a non-volatile substance B is added to the solvent, its vapour pressure drops to 0.60 atm.
Mole fraction of the component B in the solution is:

1. 0.50 2. 0.75
3. 0.40 4. 0.25
Subtopic:  Relative Lowering of Vapour Pressure |
 72%
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
Links
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

The lowest boiling point, if concentration is fixed at 0.1 M in aqueous solution, is given by which of the following solutions?

a. K2SO4

b. NaCl

c. Urea

d. Glucose

1. a, b

2. b, c

3. c, d

4. d, a

Subtopic:  Elevation of Boiling Point |
 64%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh