JEE Main 2025 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 8 April 2025, Shift 2, Chemistry Q74

Question 74 of 75 in this shift, Chemistry question 24 of 25, Section B.

The equilibrium constant for decomposition of

\mathrm{H_2O}

(g)

\mathrm{H_2O(g) \rightleftharpoons H_2(g) + \frac{1}{2}O_2(g)}

(

\Delta G^\circ = 92.34

kJ mol

^{-1}

) is

8.0 \times 10^{-3}

at 2300 K and total pressure at equilibrium is 1 bar. Under this condition, the degree of dissociation (

\alpha

) of water is __________

\times 10^{-2}

(nearest integer value). [Assume

\alpha

is negligible with respect to 1]

Official answer

NTA final key.

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

Same idea in other shifts

Asked 4× in all

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24 Jun 2022, Shift 1 · Q64For a reaction at equilibrium $\mathrm{A(g)} \rightleftharpoons \mathrm{B(g)}+\frac{1}{2}\mathrm{C(g)}$ the relation between dissociation…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 42 of the 174 JEE Main shifts held from 2017 to 2026.