JEE Main 2021ChemistryRedox ReactionsMediumNumerical

JEE Main 2021 — Redox Reactions Question with Solution

JEE Main 2021 (25 Jul Shift 1)

Question

When 10 mL of an aqueous solution of Fe2+ ions was titrated in the presence of dil H2SO4 using diphenylamine indicator, 15 mL of 0.02 M solution of K2Cr2O7 was required to get the end point. The molarity of the solution containing Fe2+ ions is x×10-2 M. The value of x is ______. (Nearest integer)

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Show full solutionCorrect answer: 18
Correct answer
18

Step-by-step explanation

milli-equivalents of Fe2+= milli-equivalents of K2Cr2O7

M×10×1=0.02×15×6

M=0.18=18×10-2 M

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About this question

This is a previous-year question from JEE Main 2021, covering the Redox Reactions 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.