JEE Main 2022 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 26 July 2022, Shift 1, Chemistry Q84

Question 84 of 90 in this shift, Chemistry question 24 of 30, Section B.

2.4 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 298 K to 300 K. The enthalpy change during the combustion of coal is

-x

kJ mol

^{-1}

. The value of

x

is __________. (Nearest Integer) (Given : Heat capacity of bomb calorimeter 20.0 kJ K

^{-1}

. Assume coal to be pure carbon)

Official answer

200

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

4 Apr 2026, Shift 2 · Q71If 3.365 g of ethanol ( $l$ ) is burnt completely in a bomb calorimeter at 298.15 K, the heat produced is 99.472 kJ. The…HardNumerical value
3 Apr 2025, Shift 2 · Q72A sample of n-octane (1.14 g) was completely burnt in excess of oxygen in a bomb calorimeter, whose heat capacity is 5 kJ…MediumNumerical value
5 Apr 2024, Shift 1 · Q83The heat of combustion of solid benzoic acid at constant volume is $-321.30$ kJ at $27^\circ$ C. The heat of combustion at constant…MediumNumerical value
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
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.