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JEE Main 26 February 2021, Shift 2, Chemistry Q54

Question 54 of 90 in this shift, Chemistry question 24 of 30, Section B.

The average S

-

F bond energy in kJ

\mathrm{mol^{-1}}

\mathrm{SF_6}

is __________. (Rounded off to the nearest integer) [Given : The values of standard enthalpy of formation of

\mathrm{SF_6}

(g), S(g) and F(g) are - 1100, 275 and 80 kJ

\mathrm{mol^{-1}}

respectively.]

Official answer

309

NTA final key.

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

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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.