JEE Main 2023 · ChemistryMultiple choiceSingle correctMediumApplication

JEE Main 13 April 2023, Shift 2, Chemistry Q64

Question 64 of 90 in this shift, Chemistry question 4 of 30, Section A.

The covalency and oxidation state respectively of boron in

[\mathrm{BF_4}]^{-}

, are

(1)4 and 4
(2)4 and 3Official answer
(3)3 and 4
(4)3 and 5

Official answer

Option 2

NTA final key.

Chapter: Chemical Bonding and Molecular Structure
Topic: Redox Reactions
Idea tested: Oxidation Number via Coordinate Bonds

Same topic in other shifts

All Redox Reactions 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 42 of the 174 JEE Main shifts held from 2017 to 2026.