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JEE Main 2021 — Some Basic Concepts of Chemistry Question with Solution

JEE Main 2021 (25 Feb Shift 1)

Question

Complete combustion of 1.80 g of an oxygen containing compound CxHyOz gave 2.64 g of CO2 and 1.08 g of H2O. The percentage of oxygen in the organic compound is :

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Show full solutionCorrect option: A
Correct answer
A53.33

Step-by-step explanation

nCO2=2.6444=0.06

nc=0.06

weight of carbon =0.06×12=0.72 gm

nH2O=1.0818=0.06

nH=0.06×2=0.12

 weight of H=0.12 gm

= 1.8 - (0.72 + 0.12)

= 0.96 gram

 % weight of oxygen =0.961.8×100

The percentage of oxygen in the organic compound = 53.3%.

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About this question

This is a previous-year question from JEE Main 2021, covering the Some Basic Concepts of Chemistry 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.