Relative Lowering of Vapour Pressure
Relative Lowering of Vapour Pressure: Overview
This topic covers concepts, such as, Relative Lowering of Vapour Pressure, Molecular Mass of a Solute through Relative Lowering of Vapour Pressure & Ostwald and Wacker's Experiment etc.
Important Questions on Relative Lowering of Vapour Pressure

The mass of a non-volatile, non-electrolyte solute (molar mass ) needed to be dissolved in 114 g octane to reduce its vapour pressure by 75 %, is:

A solution contains of urea per litre of water. Another solution contains of cane sugar per litre of water at the same temperature. What is the ratio of lowering of vapour pressure in solutions of and ?

The vapour pressure of an aqueous solution of cane sugar (molar weight=) is at . How many grams of sugar are present per of water? Report the answer in the nearest integer

What is the vapour pressure of a solution containing of water and of sucrose at ?
Give your answer by rounding off to the nearest integer value.Molecular weight of sucrose is .

The pressure of the water vapour of a solution containing a non-volatile solute is below that of the vapour of pure water. Determine the molality of the solution.
Round off your answer to nearest integer value.

An aqueous solution of non-volatile solute exerts a pressure of bar at the normal boiling point of the solvent. What is the molar mass of the solute? (Write the answer without units)

Two beaker are placed in a sealed flask. Beaker A initially contained 0.15 mol of naphthalene (non-volatile) in 117 g of benzene and beaker B initially contained 31 g of an unknown compound (non-volatile, non-electrolytic) in 117 g of benzene. At equilibrium, beaker A is found to have lost 7.8 g of weight. Assume ideal behaviour of both solutions to answer the following question.
The molar mass of solute in solution B is closest to:

Relative vapour pressure lowering depends only on.

Vapour pressure of solution of a non volatile solute is always

Lowering of the vapour pressure of the solution:

Find the value of mole fraction of the solute when vapour pressure of glucose is at in dilute solution.

Find the correct relation between of acids HA1 and HA2 (assuming they are taken in same concentration), if lowering of vapour pressure $\Delta \mathrm{P}_{1}$ of an aqueous solution of acid HA1 and $\Delta \mathrm{P}_{2}$ of an aqueous solution of acid HA2, are related as .

An ideal solution of two pure liquids and are having the vapour pressure of and respectively at the temperature . The liquid solution of and is made up of of each and . Then, find the pressure when of mixture has been vaporised.

The relative lowering of the vapour pressure of an aqueous solution containing a non-volatile solute is . What is the molality of the solution?

A solution of 2.0 g of sulphur in 100 g of CS2 has a vapour pressure of 844.9 torr. At 48oC, the vapour pressure of pure CS2 is 850 torr. Calculate the atomicity of sulphur molecule.

If two beaker and are present in a closed vessel. Beaker contains aqueous solution of urea, containing of urea. Beaker contains glucose solution, containing of glucose. Both solutions allowed to attain the equilibrium. Calculate the Weight% of glucose in its solution at equilibrium.

The vapor pressure of pure water is of at . Calculate the vapor pressure of the resulting solution when of glucose is added to of water?

Assertion : When dry air is passed continuously through an aqueous solution of a non-volatile solute, vapour pressure of solution decreases gradually.
Reason : Some air is absorbed in the solution.

The vapour pressure of water at is If of glucose is added to of water at , what will be the vapour pressure of the resulting solution?
