The equal weight of a solute is dissolved in an equal weight of two solvents A and B to form a very dilute solution. The relative lowering of vapour pressure for solution B has twice the relative lowering of vapour pressure for solution A.

If ${\mathrm{M}}_{\mathrm{A}}$ and ${\mathrm{M}}_{\mathrm{B}}$ are the molecular weights of solvents A and B respectively, then:

1. ${\mathrm{M}}_{\mathrm{A}}$ = ${\mathrm{M}}_{\mathrm{B}}$

2. ${\mathrm{M}}_{\mathrm{B}}$ = 2${\mathrm{M}}_{\mathrm{A}}$

3. ${\mathrm{M}}_{\mathrm{A}}$ = 4${\mathrm{M}}_{\mathrm{B}}$

4. ${\mathrm{M}}_{\mathrm{A}}$ = 2${\mathrm{M}}_{\mathrm{B}}$

Assertion : When 'a' mL of a 0.1 molal urea solution is mixed with another 'b' mL of 0.1 molal glucose

                   solution, the boiling point of the solution is no different from the boiling points of the

                   samples prior to mixing but if 'a' mL of 0.1 molal urea is mixed with 'b' mL of 0.1 molal HF

                   the boiling point of the mixture is different from the boiling points of the separate

                   samples.

Reason : HF is an electrolyte (weak) whereas glucose is a non electrolyte.

Assertion : The molar mass obtained for benzoic acid in benzene is found to be nearly twice

Reason : Benzoic acid has the formula $\mathrm{HOOC}$

Assertion(A): The difference in the boiling points of equimolar solution of HCI and HF decreases as their molarity is decreased.

Reason(R): The extent of dissociation decreases steadily with increasing dilution.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion 
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion 
3. Assertion is true but the reason is false 
4. Both assertion and reason are false 

Assertion :  When a cell is placed in hypertonic solution, it shrinks.

Reason : Reverse osmosis is used for desalination of water.

Assertion : Perfectly ideal solution is not possible with respect to binary solution of two liquids.

Reason : No two substances can have exactly the same nature of intermolecular forces & also of the same magnitude.

The boiling point of 0.2 mol kg^–1 solution of X in water is greater than the equimolal solution of Y in water. The correct statement in this case is:

The largest freezing point depression among the following 0.10 m solutions is shown by: