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Question
On the basis of information given below mark the correct option.
On adding acetone to methanol some of the hydrogen bonds between methanol molecules break.
Options
At specific composition methanol-acetone mixture will form minimum boiling azeotrope and will show positive deviation from Raoult’s law.
At specific composition methanol-acetone mixture forms maximum boiling azeotrope and will show positive deviation from Raoult’s law.
At specific composition methanol-acetone mixture will form minimum boiling azeotrope and will show negative deviation from Raoult’s law.
At specific composition methanol-acetone mixture will form maximum boiling azeotrope and will show negative deviation from Raoult’s law.
Solution
At specific composition methanol-acetone mixture forms maximum boiling azeotrope and will show positive deviation from Raoult’s law.
Explanation:
(i) (A-A) or (B-B) interactions are stronger than that (A-B) interactions; where, A is methanol and B represents a molecule of acetone. It means that in this solution molecules of A (or B) wil find it easier to escape/ This will increase the vapour pressure and result into positive deviation from Rault's law.
(ii) Due to this positive deviation the methaonal-acetone mixture forms minimums boiling azeotrope.
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