Question

Consider a binary mixture of volatile liquids. If at X_A = 0.4 the vapour pressure of solution i 580 torr then the mixture could be (p_Aº = 30 torr, p_B° = 800 torr) :

(A) CHCl₃ – CH₃COCH₃

(B) C₆H₅Cl – C₆H₅Br

(C) C₆H₆ – C₆H₅CH₃

(D) nC₆H₁₄ – nC₇H₁₆

Answer 1

Correct Answer is: (A) CHCl₃ – CH₃COCH₃

It shows negative deviation from Raoult’s law

p_s (actual) = 580 torr

p_s (Raoult) = 0.4 × 300 + 0.6 × 800 =600 torr.