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Friday, 9 October

JEE Main 2024 · ChemistryMultiple choiceSingle correctEasyConceptual

JEE Main 30 January 2024, Shift 2, Chemistry Q65

Question 65 of 90 in this shift, Chemistry question 5 of 30, Section A.

Reduction potential of ions are given below: ClO4−\mathrm{ClO_4^-} E∘=1.19 VE^\circ = 1.19\ V; IO4−\mathrm{IO_4^-} E∘=1.65 VE^\circ = 1.65\ V; BrO4−\mathrm{BrO_4^-} E∘=1.74 VE^\circ = 1.74\ V The correct order of their oxidising power is :
  1. (1)ClO4−>IO4−>BrO4−\mathrm{ClO_4^-} > \mathrm{IO_4^-} > \mathrm{BrO_4^-}
  2. (2)IO4−>BrO4−>ClO4−\mathrm{IO_4^-} > \mathrm{BrO_4^-} > \mathrm{ClO_4^-}
  3. (3)BrO4−>IO4−>ClO4−\mathrm{BrO_4^-} > \mathrm{IO_4^-} > \mathrm{ClO_4^-}Official answer
  4. (4)BrO4−>ClO4−>IO4−\mathrm{BrO_4^-} > \mathrm{ClO_4^-} > \mathrm{IO_4^-}

Official answer

Option 3

NTA final key.

Chapter
Electrochemistry
Topic
Nernst Equation
Idea tested
Standard Cell Potential

Same idea in other shifts

Asked 6× in all
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  3. 9 Apr 2024, Shift 1 · Q85The standard reduction potentials at 298 K for the following half cells are given below :…MediumNumerical value
  4. 28 Jul 2022, Shift 1 · Q70Which of the following has least tendency to liberate H2\mathrm{H_2} from mineral acids ?EasySingle correct
  5. 2 Apr 2017 (offline) · Q36Given ECl2/Cl−∘=1.36E^\circ_{\mathrm{Cl_2/Cl^-}}=1.36 V, ECr3+/Cr∘=−0.74E^\circ_{\mathrm{Cr^{3+}/Cr}}=-0.74 V ECr2O72−/Cr3+∘=1.33E^\circ_{\mathrm{Cr_2O_7^{2-}/Cr^{3+}}}=1.33 V,…EasySingle 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 42 of the 174 JEE Main shifts held from 2017 to 2026.