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JEE Main 13 April 2023, Shift 1, Chemistry Q83

Question 83 of 90 in this shift, Chemistry question 23 of 30, Section B.

\mathrm{A_2}+\mathrm{B_2}\rightarrow 2\mathrm{AB}

\Delta H_f^0 = -200\ \mathrm{kJ\ mol^{-1}}

AB,

\mathrm{A_2}

and

\mathrm{B_2}

are diatomic molecules. If the bond enthalpies of

\mathrm{A_2}

\mathrm{B_2}

and AB are in the ratio 1:0.5:1, then the bond enthalpy of

\mathrm{A_2}

is ___________

\mathrm{kJ\ mol^{-1}}

(Nearest integer)

Official answer

800

NTA final key.

Chapter: Thermodynamics (Chemistry)
Topic: Enthalpy and Hess's Law
Idea tested: Bond Enthalpy Calculations

Same idea in other shifts

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.