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Saturday, 31 October

JEE Main 2021 · ChemistryNumerical answerNumerical valueHardMulti-step

JEE Main 25 February 2021, Shift 1, Chemistry Q51

Question 51 of 90 in this shift, Chemistry question 21 of 30, Section B.

0.4 g mixture of NaOH, Na2CO3\mathrm{Na_2CO_3} and some inert impurities was first titrated with N10\frac{\mathrm{N}}{10} HCl using phenolphthalein as an indicator, 17.5 mL of HCl was required at the end point. After this methyl orange was added and titrated. 1.5 mL of same HCl was required for the next end point. The weight percentage of Na2CO3\mathrm{Na_2CO_3} in the mixture is ________. (Rounded-off to the nearest integer)

Official answer

4

NTA final key.

Chapter
Some Basic Concepts of Chemistry
Topic
Stoichiometry
Idea tested
Composition of Solid Mixtures

Same topic in other shifts

All Stoichiometry questions
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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.