Learn

Saturday, 31 October

JEE Main 2021 · ChemistryMultiple choiceTwo statementsMediumConceptual

JEE Main 24 February 2021, Shift 1, Chemistry Q50

Question 50 of 90 in this shift, Chemistry question 20 of 30, Section A.

Given below are two statements : Statement I : Colourless cupric metaborate is reduced to cuprous metaborate in a luminous flame. Statement II : Cuprous metaborate is obtained by heating boric anhydride and copper sulphate in a non-luminous flame. In the light of the above statements, choose the most appropriate answer from the options given below.
  1. (1)Both Statement I and Statement II are true
  2. (2)Both Statement I and Statement II are falseOfficial answer
  3. (3)Statement I is true but Statement II is false
  4. (4)Statement I is false but Statement II is true

Official answer

Option 2

NTA final key.

Chapter
The p-Block Elements
Topic
Group 13 & 14
Idea tested
Borax Bead Test Chemistry

Same idea in other shifts

Asked 2× in all
  1. 2 Apr 2026, Shift 2 · Q70Among Fe2+^{2+}, Fe3+^{3+}, Cr2+^{2+} and Zn2+^{2+}, the ion that shows positive borax bead test and with highest ionisation enthalpy is:MediumSingle correct

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.