JEE Main 2024 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 5 April 2024, Shift 1, Chemistry Q83

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

The heat of combustion of solid benzoic acid at constant volume is

-321.30

kJ at

27^\circ

C. The heat of combustion at constant pressure is

(-321.30 - xR)

kJ, the value of

x

is ________.

Official answer

150

NTA final key.

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

Same idea in other shifts

Asked 7× in all

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8 Apr 2023, Shift 2 · Q83For complete combustion of ethene, $\mathrm{C_2H_4(g) + 3O_2(g) \rightarrow 2CO_2(g) + 2H_2O(l)}$ the amount of heat produced as measured…MediumNumerical value
26 Jul 2022, Shift 1 · Q842.4 g coal is burnt in a bomb calorimeter in excess of oxygen at 298 K and 1 atm pressure. The temperature of the calorimeter rises from…MediumNumerical value
27 Jul 2022, Shift 2 · Q83A gas (Molar mass=280 g $\mathrm{mol^{-1}}$ ) was burnt in excess $\mathrm{O_2}$ in a constant volume calorimeter and during combustion the…MediumNumerical value
25 Feb 2021, Shift 1 · Q53The reaction of cyanamide, $\mathrm{NH_2CN_{(s)}}$ with oxygen was run in a bomb calorimeter and $\Delta U$ was found to be $-742.24$ kJ…MediumNumerical value

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.