Question

Which of the following plots does not represent the behaviour of an ideal binary liquid solution?

• A. Plot of $P_A$ versus $X_A$ (mole fraction of A in liquid phase) is linear
• B. Plot of $P_B$ versus $X_B$ is linear
• C. Plot of $p_{total}$ versus $X_A$ or ($X_B$) is linear
• D. Plot of $p_{total}$ versus $X_A$ is non linear

Answer 1

The correct option is D Plot of $p_{total}$ versus $X_A$ is non linear

We know, from Raoult's Law , $P_T=P_a^{\prime }+P_b^{\prime }$

where, $P_a^{\prime }+P_b^{\prime }=X_A{P}_a^{\circ }+X_B{P}_b^{\circ }$

Also, $X_A+X_B=1$

$\therefore P_T=X_A[P_a^{\circ }-P_b^{\circ }]+P_b^{\circ }$

$P_T$ Vs $X_A$ is a linear plot.