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JEE Main 26 June 2022, Shift 1, Chemistry Q81

Question 81 of 90 in this shift, Chemistry question 21 of 30, Section B.

For complete combustion of methanol

\mathrm{CH_3OH(l)}+\frac{3}{2}\mathrm{O_2(g)}\rightarrow\mathrm{CO_2(g)}+2\mathrm{H_2O(l)}

the amount of heat produced as measured by bomb calorimeter is 726 kJ mol

^{-1}

at 27°C. The enthalpy of combustion for the reaction is

-x

kJ mol

^{-1}

, where

x

is __________. (Nearest integer) (Given : R=8.3 JK

^{-1}

mol

^{-1}

)

Official answer

727

NTA final key.

Chapter: Thermodynamics (Chemistry)
Topic: Enthalpy and Hess's Law
Idea tested: Relation Between ΔH and ΔU

Same idea in other shifts

Asked 10× 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.