JEE Main 2021 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 25 February 2021, Shift 1, Chemistry Q54

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

1 molal aqueous solution of an electrolyte

\mathrm{A_2B_3}

is 60% ionised. The boiling point of the solution at 1 atm is ________ K. (Rounded-off to the nearest integer) [Given

\mathrm{K_b}

for

\mathrm{(H_2O)} = 0.52

K kg mol

^{-1}

]

Official answer

375

NTA final key.

Chapter: Solutions
Topic: Colligative Properties
Idea tested: Van't Hoff Factor (i)

Same idea in other shifts

Asked 7× 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.