JEE Main 2021 · ChemistryNumerical answerNumerical valueMediumMulti-step

JEE Main 26 February 2021, Shift 1, Chemistry Q55

Question 55 of 90 in this shift, Chemistry question 25 of 30, Section B.

A homogeneous ideal gaseous reaction

\mathrm{AB_{2(g)} \rightleftharpoons A_{(g)} + 2B_{(g)}}

is carried out in a 25 litre flask at 27°C. The initial amount of

\mathrm{AB_2}

was 1 mole and the equilibrium pressure was 1.9 atm. The value of

\mathrm{K_p}

x\times10^{-2}

. The value of

x

is __________. (Integer answer) [R = 0.08206 dm

^3

atm K

^{-1}

mol

^{-1}

]

Official answer

NTA final key.

Chapter: Equilibrium
Topic: Chemical Equilibrium
Idea tested: Degree of Dissociation

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Asked 5× 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.