JEE Main 2021 · ChemistryMultiple choiceSingle correctEasyConceptual

JEE Main 17 March 2021, Shift 2, Chemistry Q33

Question 33 of 90 in this shift, Chemistry question 3 of 30, Section A.

For the coagulation of a negative sol, the species below, that has the highest flocculating power is :

(1) $\mathrm{Ba^{2+}}$ Official answer
(2) $\mathrm{Na^+}$
(3) $\mathrm{PO_4^{3-}}$
(4) $\mathrm{SO_4^{2-}}$

Official answer

Option 1

NTA final key.

Chapter: Surface Chemistry
Topic: Colloids
Idea tested: Hardy-Schulze Rule

Same idea in other shifts

Asked 5× 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.