JEE Main 2019ChemistryThermodynamics (C)MediumMCQ

JEE Main 2019 — Thermodynamics (C) Question with Solution

JEE Main 2019 (10 Apr Shift 2)

Question

The difference between ∆H and ∆U is ∆H-∆U, when the combustion of one mole of heptane l is carried out at a temperature T , is equal to:

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Show full solutionCorrect option: A
Correct answer
A-4RT

Step-by-step explanation

Combustion of heptane

C7H16l+11O2g⟶7CO2g+8H2Ol

∆H=∆U+∆ngRT

∆H-∆U=∆ngRT

∴∆ng=7-11=-4

=-4×RT

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About this question

This is a previous-year question from JEE Main 2019, covering the Thermodynamics (C) chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.