JEE Main 2021ChemistrySolutionsMediumNumerical

JEE Main 2021 — Solutions Question with Solution

JEE Main 2021 (16 Mar Shift 2)

Question

At 363 K, the vapour pressure of A is 21 kPa and that of B is 18kPa. One mole of A and 2 moles of B are mixed. Assuming that this solution is ideal, the vapour pressure of the mixture is___________ kPa. (Round of to the Nearest Integer).

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Show full solutionCorrect answer: 19
Correct answer
19

Step-by-step explanation

Given PA0=21 kPa  ⇒PB0=18 kPa

→ An Ideal solution is prepared by mixing 1 mole A and 2 mole B.

→XA=13 and XB=23

→ According to Raoult's law

PT=XAPA0+XBPB0

⇒  PT=13×21+23×18

⇒  PT=7+12=19 kPa

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About this question

This is a previous-year question from JEE Main 2021, 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.