Vapour pressure of ethanol and methanol are 44.5 mmHg and 88.7 mmHg respectively .At the same temperature 60 gm of ethanol is mixed with 40 gm of methanol forming an ideal solution.Calculation the vapour pressure of mixture.

Options

A. 68 mm
B. 66.13 mm
C. 73.4 mm
D. 75.3 mm

Answer

B

Explanation

`P_(m)=P_(B)^(0)x_(A)+P_(B)x_(B)^(0)`
`P_(m)=44.5xx((60)/(46))/((60)/(46)+(40)/(32))+88.7xx((40)/(32))/((40)/(32))`
`=66.13 "nm"`