Question

The mole fraction of component A in vapour phase is $x_1$ and mole fraction of component A in liquid mixture is $x_2$ $(P_A^0=$ vapour pressure of pure A, $P_B^0=$ vapour pressure of pure B). Then total vapour pressure of the liquid mixture is:-

• A. $\frac{P_A^0{x}_2}{x_1}$
  
• B. $\frac{P_A^0{x}_1}{x_2}$
  
• C. $\frac{P_B^0{x}_1}{x_2}$
  
• D. $\frac{P_B^0{x}_2}{x_1}$

Answer 1

The correct option is A $\frac{P_A^0{x}_2}{x_1}$


$P_{total}{x}_1=P_A^0{x}_2$

$\therefore P_{total}=\frac{P_A^0{x}_A}{x_1}$