8. Identify the mixture that shows positive deviation from Raoult’s law a

a. CHCl₃  + (CH₃ )2  CO

b. (CH₃ )2  CO +  C₆ H₅ NH₂

c. CHCl₃  + C₆ H₆

d.(CH₃ )2  CO + CS₂ 

e. C₆ H₅ N + CH₃  COOH

ANSWER : D

Explanation : Acetone is a polar solvent where as  CS₂ is a non polar solvent The cohesive forces are stronger than adhesive forces in the solution so it will increase the vapour pressure as against the prediction by Raoult’s law. So it will show a positive deviation. Due to formation of hydrogen bonds between diefferent molecules of different components in option a, b, c and e these compound will show negative deviation from Raoult’s law.

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