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Saturday, 31 October

JEE Main 2021 · ChemistryMultiple choiceAssertion–reasonMediumRecall

JEE Main 26 August 2021, Shift 2, Chemistry Q36

Question 36 of 90 in this shift, Chemistry question 6 of 30, Section A.

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Heavy water is used for the study of reaction mechanism. Reason (R) : The rate of reaction for the cleavage of O−H\mathrm{O-H} bond is slower than that of O−D\mathrm{O-D} bond. Choose the most appropriate answer from the options given below :
  1. (1)Both (A) and (R) are true and (R) is the true explanation of (A).
  2. (2)Both (A) and (R) are true but (R) is not the true explanation of (A).
  3. (3)(A) is true but (R) is false.Official answer
  4. (4)(A) is false but (R) is true.

Official answer

Option 3

NTA final key.

Chapter
Hydrogen

Same idea in other shifts

Asked 2× in all
  1. 13 Apr 2023, Shift 2 · Q66Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Isotopes of hydrogen…MediumAssertion–reason

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.