Raoult's Law

IMPORTANT

Raoult's Law: Overview

This Topic covers sub-topics such as Raoult's Law, Applications of Raoult's law, Mole Fraction in Vapour Phase, Vapour Pressure of Solutions of Solids in Liquids and, Raoult's Law for a Solution Containing a Non-Volatile Solute in a Liquid

Important Questions on Raoult's Law

MEDIUM
IMPORTANT

Under what condition Henry's law becomes special case of Raoult's Law?

MEDIUM
IMPORTANT

For a binary ideal liquid solution, the variation in total vapour pressure versus composition of solution is given by which of the curves?

HARD
IMPORTANT

An aqueous solution is made by dissolving 10g of glucose C6H12O6 in 90g of water at 300 K. If the vapour pressure of pure water at 300 K is 32.8 mm Hg, what would be the vapour pressure of the solution?

MEDIUM
IMPORTANT

What changes occurs in the vapour pressure as a non-volatile solute is added to a pure liquid solvent?

EASY
IMPORTANT

Two liquids are mixed together to form a mixture which boils at same temperature and their boiling point is higher than the boiling point of either of them, so they show _____ from Raoult's law.

EASY
IMPORTANT

The vapour pressure of the solution is affected by adding the _____ solute.

EASY
IMPORTANT

When will the vapour pressure of the volatile liquid lowered?

HARD
IMPORTANT

The vapour pressure of water is 12.3kPa at 300 k. Now, calculate the vapour pressure of 1 molar solution of a solute in it.

HARD
IMPORTANT

_____ law which states that for a solution of volatile liquids, the partial vapour pressure of each component of the solution is directly proportional to its mole fraction present in solution.

HARD
IMPORTANT

The following is a graph plotted between the vapour pressure of two volatile liquids against their respective mole fractions.

Question Image

Which of the following statement is correct ?

MEDIUM
IMPORTANT

For a dilute solution containing 2.5 g of a non-volatile non-electrolyte solution in 100 g of water, the elevation in boiling point at 1atm pressure is 2°C. Assuming the concentration of solute is much lower than the concentration of the solvent, the vapor pressure of the solution is (Kb = 0.76 K kg mol-1)

MEDIUM
IMPORTANT

Two liquids X and Y form an ideal solution. At 300 K, vapour pressure of the solution containing 1 mole of X and 3 mole of Y is 550 mm Hg. At the same temperature, if1  mole of Y is further added to this solution, vapour pressure of the solution increases by10 mm Hg . Vapour pressure (in mm Hg) of X and Y in their pure states will be, respectively

MEDIUM
IMPORTANT

The vapours pressure of pure components X and Y are 200 torr and 100 torr respectively. Assuming a solution of these components obeys Raoult's law, the mole fraction of component X in the vapours phase in equilibrium with a solution containing equimolecular of X and Y is

EASY
IMPORTANT

30 g of urea M=60 g mol-1 is dissolved in 846 g of water. Calculate the vapour pressure of water for this solution if vapour pressure of pure water at 298 K is 23.8 mmHg.

EASY
IMPORTANT

Which of the following units is most useful in relating concentration of solution with its vapour pressure?

EASY
IMPORTANT

When partial pressure of solvent in solution of non-volatile solute is plotted against its mole fraction, nature of graph is

EASY
IMPORTANT

Partial pressure of solvent (mole fraction=x1) in solution of non-volatile solute (mole fraction=x2) is given by equation,

HARD
IMPORTANT

Explain the determination of molar mass of a solute from relative lowering in vapour pressure.

MEDIUM
IMPORTANT

In an equilibrium at 300C with a benzene-toluene solution, the mole fraction of benzene is 0.400, then, what is the mole fraction of toluene in vapour phase?

PB0=119 torr and Pr0=37.0 torr

EASY
IMPORTANT

Maximum boiling azeotrope will be formed by-