Question

Equal masses of a solute are dissolved
in equal amount of two solvents A and
B, respective molecular masses being
MA and Ms. The relative lowering of
vapour pressure of solution in solvent A
is twice that of the solution in solvent B.
If the solutions are dilute, MA and MB
are related as
A
MA = MB
B
2MA = MB
C
MA = 2MB
D
MA = 4MB​

Answer 1

Answer:mb=2*ma

Explanation:

Since relative lowering of vapor pressure for B = 2 times of A

This means solute mole fraction in B= 2*solute mole fraction in A  

w/Ms/(w/Mb) =2*w/Ms/(w/Ma)  

Assuming mole fraction of solute is very small in comparison of solvent

Solving we get Mb=2*Ma