Question

The vapour pressure of benzene, toluene and xylene are $75$ torr, $22$ torr and $10$ torr at ${20}^{0}C$. Which of the following is not a possible value of the vapour pressure of an equimolar binary/ ternary solution of these at ${20}^{o}C$?

Take all solutions as ideal in nature (Give approximate answer)

Answer 1

x benzene$=0.34$

x toluene$=0.66$

w.k.t; $P_{sol}=x_{benzene}\cdot P_{benzene}$

$+xtoluene.P^{o}toluene$

$x_b+x_t=1$

$x=1-y$ and,

$P_{total}=x.75+(1\ne x).22$

$40=x.75+(1-x).22$

$40=75x+22-22x$

$x=\frac{18}{53}=0.3396=0.34$

$y=1-x=0.66$

$\therefore$ x benzene$=0.34$

x toluene$=0.66$.