JEE Main 2015 — Solutions Question with Solution
From: JEE Main 2015 (Offline)
Question
The vapour pressure of acetone at 20oC is 185 torr. When 1.2 g of a non-volatile substance was dissolved in
100 g of acetone at 20oC, its vapour pressure was 183 torr. The molar mass (g mol-1) of the substance is:
Choose an option
Show full solutionCorrect option: A
Correct answer
A64
Step-by-step explanation
Using relation,
where mass in
and mol. mass of solvent
mass in
and mol. mass of solute
Let
(Mol. mass of acetone )
Molar mass of substance
where mass in
and mol. mass of solvent
mass in
and mol. mass of solute
Let
(Mol. mass of acetone )
Molar mass of substance
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This is a previous-year question from JEE Main 2015, covering the Solutions chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.