A solution of urea (molar mass 56 g mol–1) boils at 100.18 ºC at atmospheric pressure. If Kf and Kb for water are 1.86 and 0.512 K kg mol–1 respectively, the above solution will freeze at:

1. –6.54 ºC

2. –0.654 ºC

3. 6.54 ºC

4. 0.654 ºC

Subtopic:  Elevation of Boiling Point | Depression of Freezing Point |
75%
From NCERT
AIPMT - 2005
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The freezing point depression constant for water is 1.86 oC m-1. If 5.00 g Na2SOis dissolved in 45.0 g H2O, the freezing point is changed by -3.82 oC. The van’t Hoff factor for Na2SO4 is:

 1 2.63 2 3.11 3 0.381 4 2.05
Subtopic:  Depression of Freezing Point |
69%
From NCERT
AIPMT - 2011
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45 g of ethylene glycol (C2H6O2) is mixed with 600 g of water. The freezing point of the solution is:

1. 268.15 K
2. 270.95 K
3. 272.75 K
4. 267.15 K

Subtopic:  Depression of Freezing Point |
63%
From NCERT
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Glucose is added to 1 litre of water to such an extent that $$\Delta T_f/K_f$$ becomes equal to 1/1000. The amount of glucose added is-

1. 180 g
2. 18 g
3. 1.8 g
4. 0.18 g
Subtopic:  Depression of Freezing Point |
78%
From NCERT
 1 Raoult's law states that the vapour pressure of a component over a solution is proportional to its mole fraction. 2 The osmotic pressure ($$\pi$$) of a solution is given by the equation $$\pi$$=MRT, where M is the molarity of the solution. 3 The correct order of osmotic pressure for 0.10 M aqueous solution of each compound is BaCl2 > KCl > CH3COOH > sucrose. 4 Two sucrose solutions of the same molarity prepared in different solvents will have the same depression in the freezing point.