JEE Main 2021 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 24 February 2021, Shift 2, Chemistry Q57

Question 57 of 90 in this shift, Chemistry question 27 of 30, Section B.

Sucrose hydrolyses in acid solution into glucose and fructose following first order rate law with a half-life of 3.33 h at

25^\circ

C. After 9 h, the fraction of sucrose remaining is

f

. The value of

\log_{10}\left(\frac{1}{f}\right)

is __________

\times 10^{-2}

. (Rounded off to the nearest integer) [Assume : ln 10

= 2.303

, ln 2

= 0.693

]

Official answer

NTA final key.

Chapter: Chemical Kinetics
Topic: Integrated Rate Equations
Idea tested: First Order Integrated Rate Law

Same idea in other shifts

Asked 13× in all

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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.