JEE Main 2021 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 24 February 2021, Shift 1, Chemistry Q56

Question 56 of 90 in this shift, Chemistry question 26 of 30, Section B.

At 1990 K and 1 atm pressure, there are equal number of

\mathrm{Cl_2}

molecules and Cl atoms in the reaction mixture. The value of

K_p

for the reaction

\mathrm{Cl_{2(g)} \rightleftharpoons 2Cl_{(g)}}

under the above conditions is

x \times 10^{-1}

. The value of

x

is __________. (Rounded off to the nearest integer)

Official answer

NTA final key.

Chapter: Equilibrium
Topic: Chemical Equilibrium
Idea tested: Kp for PCl5 Dissociation Type Reactions

Same idea in other shifts

Asked 4× in all

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2 Apr 2025, Shift 2 · Q55Consider the following chemical equilibrium of the gas phase reaction at a constant temperature :…MediumSingle correct
31 Jan 2024, Shift 2 · Q64 $\mathrm{A_{(g)}\rightleftharpoons B_{(g)}+\frac{C}{2}{}_{(g)}}$ The correct relationship between $\mathrm{K_p}$ , $\alpha$ and equilibrium…MediumSingle correct

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.