JEE Main 2018ChemistryChemical KineticsMediumMCQ

JEE Main 2018 — Chemical Kinetics Question with Solution

JEE Main 2018 (08 Apr)

Question

At 518oC, the rate of decomposition of a sample of gaseous acetaldehyde, initially at a pressure of 363 Torr was 1.00 Torr s-1 when 5% had reacted and 0.50 Torr s-1 when 33% had reacted. The order of the reaction is:

Choose an option

Show full solutionCorrect option: B
Correct answer
B2

Step-by-step explanation

Rate∝concentrationn

Let the initial concentration be 1 M.

According to the question,

Concentration  Rate0.95 M10.67 M 0.5

Substituting in the general rate expression,

0.950.67n=10.5

⇒n=2

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About this question

This is a previous-year question from JEE Main 2018, covering the Chemical Kinetics 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.