A solution M is prepared by mixing ethanol and water. The mole fraction of ethanol in the mixture is 0.9. Given
`k_(f)("water")=1.86Kkg"mol"^(-1)`
`k_(f)("ethanol")=2.0Kkg"mol"^(-1)`
`k_(b)("water")=0.52Kkg"mol"^(-1)`
`k_(b)("ethanol")=1.2Kkg"mol"^(-1)`
Standard f.p. of water = 273 K
Standard f.p. of ethanol = 155.7 K
Standard b.p. of water = 373 K
Standard b.p. of ethanol = 351.5 K
Vapour pressure of pure water = 32.8 mmHg
Vapour pressure of pure ethanol = 40 mmHg
Molecular weight of water = 18 g `"mol"^(-1)`
Molecular weight of ethanol = 46 g `"mol"^(-1)`
consider the solutions to be ideal dilute solutions and solutes to be nonvolatile and non-dissociative.
Water is added to the solution M such that the mole fraction of water in the solution becomes 0.9. The b.p. of this solution is

Options

A. 380.4 K
B. 376.2 K
C. 375.5 K
D. 354.7 K

Answer

B

Explanation

Solute is ethanol and solvent is water