JEE Main 2022ChemistryThermodynamics (C)HardNumerical

JEE Main 2022 — Thermodynamics (C) Question with Solution

JEE Main 2022 (27 Jul Shift 2)

Question

A gas ( Molar mass =280 g mol-1) was burnt in excess O2 in a constant volume calorimeter and during combustion the temperature of calorimeter increased from 298.0 K to 298.45 K. If the heat capacity of calorimeter is 2.5 kJ K-1 and enthalpy of combustion of gas is 9 kJ mol-1 then amount of gas burnt is____g.

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Show full solutionCorrect answer: 35
Correct answer
35

Step-by-step explanation

Let x g is burnt

Moles=x280 heat released by x280 mole=2.5×0.45 kJ heat released by 1 mole =2.5×0.45×280xkJ

ΔH=ΔU+ΔngRT

ΔH≃ΔU

9=2.5×280×0.45x

x=35 g

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About this question

This is a previous-year question from JEE Main 2022, 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.