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Friday, 9 October

NEET UG 2025 · Chemistry · Question 89

NEET 2025 Chemistry, question 89

Question 89 of the NEET 2025 paper (code 45) is a Chemistry question from Chemical Kinetics. Its idea, First Order Integrated Rate Law, was asked 4 times, in 2017, 2020, 2022 and 2025, across NEET 2017–2026. The NTA final answer key gives option 1.

Updated 2026-10-08

Q89 · Chemistry

If the rate constant of a reaction is 0.03 s−1^{-1}, how much time does it take for 7.2 mol L−1^{-1} concentration of the reactant to get reduced to 0.9 mol L−1^{-1}?

(Given: log 2 = 0.301)

  1. 169.3 sOfficial answer
  2. 223.1 s
  3. 3210 s
  4. 421.0 s

Official answer: option 1 · NTA final answer key

Same idea

First Order Integrated Rate Law, in other papers

NEET asked this idea 4 times, in 2017, 2020, 2022 and 2025. The other 3 questions below.

  • 2022 Q92For a first order reaction A →\to Products, initial concentration of A is 0.1 M, which becomes 0.001 M after 5 minutes. Rate constant for…Numerical · Easy
  • 2020 Q132The rate constant for a first order reaction is 4.606×10−34.606\times10^{-3} s−1^{-1}. The time required to reduce 2.0 g of the reactant to 0.2 g…Numerical · Easy
  • 2017 Q81A first order reaction has a specific reaction rate of 10−210^{-2} sec−1\mathrm{sec^{-1}}. How much time will it take for 20 g of the reactant…Numerical · Easy

First Order Integrated Rate Law: 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