JEE Main 2021 · ChemistryNumerical answerNumerical valueMediumMulti-step

JEE Main 17 March 2021, Shift 2, Chemistry Q54

Question 54 of 90 in this shift, Chemistry question 24 of 30, Section B.

A 1 molal

\mathrm{K_4Fe(CN)_6}

solution has a degree of dissociation of 0.4. Its boiling point is equal to that of another solution which contains 18.1 weight percent of a non electrolytic solute A. The molar mass of A is __________ u. (Round off to the Nearest Integer). [Density of water

= 1.0\ \mathrm{g\ cm^{-3}}

]

Official answer

NTA final key.

Chapter: Solutions
Topic: Colligative Properties
Idea tested: Degree of Dissociation from Van't Hoff Factor

Same idea in other shifts

Asked 6× in all

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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.