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प्रश्न
What is meant by negative deviation from Raoult's law? Give an example. What is the sign of ∆mixH for negative deviation?
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उत्तर
The non-ideal solutions that do not obey Raoult's law over the entire range of concentration and have vapour pressures lower than those predicted by Raoult's law show a negative deviation from Raoult's law.
Example: A mixture of chloroform and acetone
In case of solutions showing negative deviations, ΔmixH has a negative sign.
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संबंधित प्रश्न
Why does a solution containing non-volatile solute have higher boiling point than the pure solvent ?
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Considering the formation, breaking and strength of hydrogen bond, predict which of the following mixtures will show a positive deviation from Raoult’s law?
On the basis of information given below mark the correct option.
(A) In bromoethane and chloroethane mixture intermolecular interactions of A–A and B–B type are nearly same as A–B type interactions.
(B) In ethanol and acetone mixture A–A or B–B type intermolecular interactions are stronger than A–B type interactions.
(C) In chloroform and acetone mixture A–A or B–B type intermolecular interactions are weaker than A–B type interactions.
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