Question

At room temperature the mole fraction of a solution is 0.25 and the vapour pressure of the solvent is 0.80 atm. Then the lowering of vapour pressure is
A. 0.75
B. 0.6
C. 0.2
D. 0.8

Answer 1

Correct Answer - C
`(P^(@)-P_(s))/(P^(@)) = x_(2) :. (P^(@)-P_(s))/(0.80) = 0.25`
or `P^(@)-P_(s) = 0.20` atm