List of top Chemistry Questions on Colligative Properties asked in CBSE CLASS XII

The freezing point of one molal KCl solution, assuming KCl to be completely dissociated in water, is: ($K_f$ for water = 1.86 K kg mol$^{-1}$)

A solution of acetone in ethanol:

State Raoult’s law for a solution containing volatile components. Why is the vapour pressure of an aqueous solution of glucose lower than that of water?

Vapour pressure of pure water at 298 K is 24.8 mm Hg. Calculate the lowering in vapour pressure of an aqueous solution which freezes at –0.3°C. (K$_f$ of water = 1.86 K kg mol$^{-1}$)

A solution of glucose (molar mass = 180 g mol$^{-1}$) in water has a boiling point of 100.20°C. Calculate the freezing point of the same solution. Molal constants for water $K_f$ and $K_b$ are 1.86 K kg mol$^{-1}$ and 0.512 K kg mol$^{-1}$ respectively.

Give reasons:
(a) Cooking is faster in a pressure cooker than in an open pan.
(b) On mixing liquid X and liquid Y, volume of the resulting solution decreases. What type of deviation from Raoult's law is shown by the resulting solution?
© What change in temperature would you observe after mixing liquids X and Y?

In case of association, abnormal molar mass of solute will:

A solution containing 2 g of glucose (M = 180 g mol$^{-1}$) in 100 g of water is prepared at 303 K. If the vapour pressure of pure water at 303 K is 32.8 mm Hg, what would be the vapour pressure of the solution?

Calculate the mass of CaCl$_2$ (molar mass = 111 g mol$^{-1}$) to be dissolved in 500 g of water to lower its freezing point by 2K, assuming that CaCl$_2$ undergoes complete dissociation.

Complete the following ionic equation:
Cr₂O₇²⁻ + 14H⁺ + 6e⁻ →

Define colligative property. Which colligative property is preferred for the molar mass determination of macromolecules?

Assertion (A): When NaCl is added to water, a depression in freezing point is observed.
Reason (R): NaCl undergoes dissociation in water.

For an electrolyte undergoing association in a solvent, the van’t Hoff factor: