JEE Main 2020 · ChemistryMultiple choiceSingle correctEasyCalculation

JEE Main 6 September 2020, Shift 2, Chemistry Q44

Question 44 of 75 in this shift, Chemistry question 19 of 25.

The value of

\mathrm{K_c}

is 64 at 800 K for the reaction

\mathrm{N_2(g)+3H_2(g)\rightleftharpoons 2NH_3(g)}

The value of

\mathrm{K_c}

for the following reaction is :

\mathrm{NH_3(g)\rightleftharpoons \frac{1}{2}N_2(g)+\frac{3}{2}H_2(g)}

(1)1/64
(2)8
(3)1/8Official answer
(4)1/4

Official answer

Option 3

NTA final key (Sep 2020).

Chapter: Equilibrium
Topic: Chemical Equilibrium
Idea tested: Equilibrium Constant for Modified Equations

Same idea in other shifts

Asked 9× in all

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8 Apr 2024, Shift 1 · Q63For the given hypothetical reactions, the equilibrium constants are as follows : $\mathrm{X\rightleftharpoons Y}$ ; $K_1=1.0$ …EasySingle correct
25 Jul 2022, Shift 2 · Q63 $\mathrm{K_{a_1}}$ , $\mathrm{K_{a_2}}$ and $\mathrm{K_{a_3}}$ are the respective ionization constants for the following reactions (a),…MediumSingle correct
26 Jul 2022, Shift 1 · Q86At 298 K, the equilibrium constant is $2 \times 10^{15}$ for the reaction :…MediumNumerical value
30 Jun 2022, Shift 1 · Q64The equilibrium constant for the reversible reaction $2\mathrm{A(g)} \rightleftharpoons 2\mathrm{B(g)}+\mathrm{C(g)}$ is $\mathrm{K_1}$ …EasySingle correct
4 Sep 2020, Shift 2 · Q28If the equilibrium constant for $\mathrm{A \rightleftharpoons B + C}$ is $K_{eq}^{(1)}$ and that of $\mathrm{B + C \rightleftharpoons P}$ …EasySingle 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.