Vapor Pressure Lowering and Raoult's Law Applications
Apply Raoult's law to calculate relative lowering of vapor pressure and relate it to solution concentration.
Why this shows up in the exam
Exams test your ability to use vapor pressure data to determine solution properties and concentrations.
How NEET tests this
Practise it
These are real questions from past NEET papers that test this exact idea.
The vapour pressure of a solvent decreased by 10 mm of mercury when a non-volatile solute was added to the solvent. The mole fraction of the solute in the solution is 0.2. What should be the mole fraction of the solvent if the decrease in the vapour pressure is to be 20 mm of mercury?
Push further
More challenging5 harder questions built from the past papers above — a step up in difficulty, with distractors designed so you can't get there by elimination. Written and checked by our reviewers, not from a real paper.
A non-volatile solute is dissolved in a pure solvent. Which of the following actions will lead to an increase in the vapour pressure of the resulting solution?
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