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Friday, 9 October

NEET UG 2017 · Chemistry · Question 88

NEET 2017 Chemistry, question 88

Question 88 of the NEET 2017 paper (code A) is a Chemistry question from Chemical Kinetics. Its idea, Rate Law from Fast Pre-Equilibrium Mechanisms, was asked only this once in NEET 2017–2026. The CBSE official answer key gives option 4.

Updated 2026-10-08

Q88 · Chemistry

Mechanism of a hypothetical reaction X2+Y2→2XY\mathrm{X_2 + Y_2 \to 2XY} is given below

(i) X2→X+X\mathrm{X_2 \to X + X} (fast)

(ii) X+Y2⇌XY+Y\mathrm{X + Y_2 \rightleftharpoons XY + Y} (slow)

(iii) X+Y→XY\mathrm{X + Y \to XY} (fast)

The overall order of the reaction will be

  1. 11
  2. 22
  3. 30
  4. 41.5Official answer

Official answer: option 4 · CBSE official answer key

Same idea

The only question on Rate Law from Fast Pre-Equilibrium Mechanisms

No other NEET paper from 2017–2026 tested this exact idea.

Rate Law from Fast Pre-Equilibrium Mechanisms: every question and how it was framed

The chapter

Chemical Kinetics in ten years of NEET

21 questions from 2017–2026, asked in 10 of 10 papers, about 2.0 a paper. Chemical Kinetics alone had 21.

Chapter analysisStudy this chapterPractise this chapter

Chemical Kinetics: questions per paper

0242’172’182’192’202’212’222’233’242’252’26