A solution of urea (mol. mass 56g mol^-1) boils at 100.18°C at the atmospheric pressure. If k_f and k_b for water are 1.86 and 0.512 K kg mol^-1 respectively, the above solution will freeze at

• -6.54°C

• 6.54°C

• 0.654°C

• - 0.654°C

If the solubility of an aqueous solution of Mg(OH)₂ , be X mole litre then k_sp of Mg(OH)₂ is:

• 4X³

• 108X⁵

• 27X⁴

• 9X

A storage battery contains a solution of H₂SO₄ 38% by weight. At this concentration, the van't Hoff factor is 2.50. At what temperature will the battery contents freeze? (K_f =1.80 mol' kg)

• 243.92 K

• 298 K

• 240.92 K

• 273 K

The freezing point depression of 0.001 m K_x[Fe(CN)₆] is 7.1x 10^-3 K. The value of x will be [Given, K_f = 1.86 KKg mol^-1 for water].

• 2

• 4

• 3

• 1

The Ka of an acid is 3.2 x 10^-5. The degree of dissociation of the acid at concentration of 0.2 M is

• 6.0 x 10^-2

• 1.26 x 10^-2

• 4.0 x 10^-2

• 0.04 x 10^-3

256.

Addition of a non-volatile solute causes lowering in vapour pressure of a solvent from 0.8 atm to 0.2 atm. What is the
mole fraction of solvent?

• 0.25

• 0.75

• 0.50

• Cannot be predicted

What would be the freezing point of aqueous solution containing 17g of C₂H₅OH in 1000 g of water?

• 0.34°C

• 0.0°C

• -0.34°C

• -0.69°C

The pH of a solution is 5.0. If H⁺ ion concentration is decreased 100 times. Then the solution will be :

• neutral

• more acidic

• basic

• of the same acidity

At a temperature, vapour pressure of pure benzene is 640 mm Hg. On dissolving 2.175 g of a non-volatile solid solute in 39.0 g benzene, vapour pressure of the solution if found to be 600 mm Hg. The molecular mass of solute is:

• 65.25

• 54.94

• 63.55

• 87.62

50 cm³ ethylene glycol is dissolved in 50 g water. Freezing point of solution is -34°C. Assuming ideal behaviour than density of ethylene glycol is (for water , K_f =1.86 K kg mol^-1)

• 1.273 g/cm³

• 2.173 g/cm³

• 1.133 g /cm³

• 2.612 g/cm³