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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