JEE Main 2023ChemistryHydrocarbonsMediumMCQ

JEE Main 2023 — Hydrocarbons Question with Solution

JEE Main 2023 (29 Jan Shift 2)

Question

When a hydrocarbon A undergoes combustion in the presence of air, it requires 9.5 equivalents of oxygen and produces 3 equivalents of water. What is the molecular formula of A?

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Correct answer
AC8H6

Step-by-step explanation

CxHy+x+y4O2→xCO2+y2H2O

Number of equivalents of O2 = Number of equivalents of H2O

Number of equivalents of H2O = y2=3 ⇒ y = 6

Number of equivalents of O2 = x+y4= 9.5

⇒x + 64 = 9.5

⇒ x + 1.5 = 9.5

⇒ x = 9.5 - 1.5 = 8

⇒x=8, y=6.

So, the formula is C8H6.

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About this question

This is a previous-year question from JEE Main 2023, covering the Hydrocarbons 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.