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Friday, 9 October

JEE Main Chemistry · Class 11

Thermodynamics (Chemistry): JEE Main previous year questions

Thermodynamics (Chemistry) had 51 questions in the 42 JEE Main shifts Lumi analysed, about 1.1 a shift, asked in 40 of 42 shifts. It ranks 10 of 30 Chemistry chapters by questions; 10% of its questions were hard.

Questions
51
in 40 of 42 shifts
A shift, on average
1.1
of 25 Chemistry questions
Since 2024
+0.1
1.1 a shift in 2017–23, 1.2 in 2024–26
Numerical answer
30
59% of its questions

Year by year

How often it came

Questions in the analysed shifts of each year. Years differ in how many shifts Lumi analysed, so read the bars with the shift count.

Questions each year
07142’173’204’214’226’239’2410’2513’26

2017: 1 shifts · 2020: 4 shifts · 2021: 4 shifts · 2022: 4 shifts · 2023: 4 shifts · 2024: 8 shifts · 2025: 8 shifts · 2026: 9 shifts

Difficulty by year
  • 20172
  • 20203
  • 20214
  • 20224
  • 20236
  • 20249
  • 202510
  • 202613
  • Easy
  • Medium
  • Hard

Inside the chapter

Topics and the ideas that repeat

6 topics and 25 distinct ideas; 6 ideas were asked more than once. Most questions are numerical value and calculation.

Topics, by questions

13 questions had no close topic in our taxonomy and are counted for the chapter only.

Ideas asked most
6 repeat

Study it on Lumi

Thermodynamics: the interactive lesson

Every question

All 51 Thermodynamics (Chemistry) questions

Newest first. Each opens with its options and the official answer.

2026 13 questions

  1. 2 Apr 2026, Shift 1 · Q54Consider the following data. (i) 2Al(s)+6HCl(aq)→Al2Cl6(aq)+3H2(g)+1200\mathrm{2Al(s)+6HCl(aq)\rightarrow Al_2Cl_6(aq)+3H_2(g)}+1200 kJ/mol (ii)…HardSingle correct
  2. 2 Apr 2026, Shift 1 · Q75At the transition temperature TT, A⇌B\mathrm{A\rightleftharpoons B} and ΔG0=105−35log⁡T\Delta G^0=105-35\log T where A and B are two states of…MediumNumerical value
  3. 2 Apr 2026, Shift 2 · Q54Gas 'A' undergoes change from state 'X' to state 'Y'. In this process, the heat absorbed and work done by the gas is 10 J and 18 J…MediumSingle correct
  4. 4 Apr 2026, Shift 1 · Q54Given below are two statements: Statement I: For an ideal gas, heat capacity at constant volume is always greater than the heat capacity…EasyTwo statements
  5. 4 Apr 2026, Shift 2 · Q71If 3.365 g of ethanol (ll) is burnt completely in a bomb calorimeter at 298.15 K, the heat produced is 99.472 kJ. The…HardNumerical value
  6. 4 Apr 2026, Shift 2 · Q72For the following reaction at 50 ∘^\circC and at 2 atm pressure, 2N2O5(g)⇌2N2O4(g)+O2(g)\mathrm{2N_2O_5(g)\rightleftharpoons2N_2O_4(g)+O_2(g)}…HardNumerical value
  7. 5 Apr 2026, Shift 1 · Q74The values of pressure equilibrium constant recorded at different temperatures for the following equilibrium reaction have been given…MediumNumerical value
  8. 5 Apr 2026, Shift 2 · Q54Consider the following data for the reaction X2(g)+Y2(g)⇌2XY(g)\mathrm{X_2(g)+Y_2(g)\rightleftharpoons 2XY(g)} at 600 K. The ΔrG⊖\Delta_r G^\ominus (in kJ…MediumSingle correct
  9. 5 Apr 2026, Shift 2 · Q55The correct order of molar heat capacities measured at 298 K and 1 bar is :MediumSingle correct
  10. 6 Apr 2026, Shift 1 · Q55Arrange the following isothermal processes in order of the magnitude of the work (p −- V) involved between states 1 and 2. A. Expansion…MediumSingle correct
  11. 6 Apr 2026, Shift 1 · Q75Consider the reaction X⇌Y\mathrm{X\rightleftharpoons Y} at 300 K. If ΔHθ\Delta H^\theta and K are 28.40 kJ mol−1^{-1} and 1.8×10−71.8\times10^{-7}…MediumNumerical value
  12. 6 Apr 2026, Shift 2 · Q54Match List - I with List - II. Given V1V_1 and V2V_2 are initial and final volumes respectively. List - I (Isothermal process) A.…MediumMatch the list
  13. 8 Apr 2026, Shift 2 · Q74Consider the reaction 2H2S(g)+3O2(g)→2H2O(l)+2SO2(g)2\mathrm{H_2S(g)} + 3\mathrm{O_2(g)} \rightarrow 2\mathrm{H_2O(l)} + 2\mathrm{SO_2(g)} The magnitude of enthalpy…EasyNumerical value

2025 10 questions

  1. 2 Apr 2025, Shift 1 · Q53Two vessels A and B are connected via stopcock. The vessel A is filled with a gas at a certain pressure. The entire assembly is immersed…MediumSingle correctHas a figure
  2. 2 Apr 2025, Shift 2 · Q53Arrange the following in order of magnitude of work done by the system/on the system at constant temperature. (a)…MediumOther
  3. 2 Apr 2025, Shift 2 · Q54Which of the following graphs correctly represents the variation of thermodynamic properties of Haber's process ?HardDiagram basedHas a figure
  4. 3 Apr 2025, Shift 1 · Q53Which of the following properties will change when system containing solution 1 will become solution 2? Solution 1: 10 mol of solute x +…MediumDiagram basedHas a figure
  5. 3 Apr 2025, Shift 1 · Q71Given : ΔHsub⊖\Delta H^{\ominus}_{sub} [C (graphite)] = 710 kJ mol−1^{-1} ΔC−HH⊖\Delta_{C-H}H^{\ominus} = 414 kJ mol−1^{-1}…MediumNumerical value
  6. 3 Apr 2025, Shift 2 · Q71A perfect gas (0.1 mol) having C‾v=1.50R\overline{\mathrm{C}}_v = 1.50\mathrm{R} (independent of temperature) undergoes the above transformation…MediumNumerical valueHas a figure
  7. 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
  8. 4 Apr 2025, Shift 2 · Q52Consider the given data : (a) HCl(g)+10 H2O(l)→HCl.10 H2O\mathrm{HCl(g)+10\ H_2O(l)\rightarrow HCl.10\ H_2O} ΔH=−69.01\Delta H=-69.01 kJ mol−1^{-1} (b)…MediumSingle correct
  9. 7 Apr 2025, Shift 1 · Q53Total enthalpy change for freezing of 1 mol of water at 10∘10^\circC to ice at −10∘-10^\circC is __________ (Given: ΔfusH=x\Delta_{fus}H = x…MediumSingle correct
  10. 7 Apr 2025, Shift 2 · Q52The correct statement amongst the following is :MediumSingle correct

2024 9 questions

  1. 6 Apr 2024, Shift 2 · Q83For the reaction at 298 K, 2A+B→C2A + B \rightarrow C, ΔH=400\Delta H = 400 kJ mol−1^{-1} and ΔS=0.2\Delta S = 0.2 kJ mol−1^{-1} K−1^{-1}. The…EasyNumerical value
  2. 8 Apr 2024, Shift 1 · Q83Consider the figure provided. 1 mol of an ideal gas is kept in a cylinder, fitted with a piston, at the position A, at 18∘18^\circ C. If…MediumNumerical valueHas a figure
  3. 9 Apr 2024, Shift 1 · Q83The heat of solution of anhydrous CuSO4\mathrm{CuSO_4} and CuSO4⋅5H2O\mathrm{CuSO_4\cdot5H_2O} are −70-70 kJ mol−1^{-1} and +12+12 kJ mol−1^{-1}…EasyNumerical value
  4. 9 Apr 2024, Shift 1 · Q84When equal volume of 1M HCl and 1M H2SO4\mathrm{H_2SO_4} are separately neutralised by excess volume of 1M NaOH solution, xx and yy kJ of…EasyNumerical value
  5. 9 Apr 2024, Shift 2 · Q83When ΔHvap=30\Delta H_{vap} = 30 kJ/mol and ΔSvap=75 J mol−1K−1\Delta S_{vap} = 75\ \mathrm{J\,mol^{-1}K^{-1}}, then the temperature of vapour, at one atmosphere…EasyNumerical value
  6. 29 Jan 2024, Shift 1 · Q62Which of the following is not correct?EasySingle correct
  7. 30 Jan 2024, Shift 2 · Q82Two reactions are given below:…EasyNumerical value
  8. 31 Jan 2024, Shift 1 · Q84Consider the following reaction at 298 K. 32O2(g)⇌O3(g)\frac{3}{2}\mathrm{O_{2(g)}} \rightleftharpoons \mathrm{O_{3(g)}}.…EasyNumerical value
  9. 31 Jan 2024, Shift 2 · Q82If 5 moles of an ideal gas expands from 10 L to a volume of 100 L at 300 K under isothermal and reversible condition then work, w, is −x-x…EasyNumerical value

2023 6 questions

  1. 6 Apr 2023, Shift 1 · Q84The value of log K for the reaction A⇌B\mathrm{A \rightleftharpoons B} at 298 K is ________. (Nearest integer) Given:…MediumNumerical value
  2. 6 Apr 2023, Shift 1 · Q86Consider the graph of Gibbs free energy G vs Extent of reaction. The number of statement/s from the following which are true with respect…MediumNumerical valueHas a figure
  3. 8 Apr 2023, Shift 2 · Q83For complete combustion of ethene, C2H4(g)+3O2(g)→2CO2(g)+2H2O(l)\mathrm{C_2H_4(g) + 3O_2(g) \rightarrow 2CO_2(g) + 2H_2O(l)} the amount of heat produced as measured…MediumNumerical value
  4. 11 Apr 2023, Shift 1 · Q83Solid fuel used in rocket is a mixture of Fe2O3\mathrm{Fe_2O_3} and Al (in ratio 1:2). The heat evolved (kJ) per gram of the mixture is…MediumNumerical value
  5. 13 Apr 2023, Shift 2 · Q62What happens when methane undergoes combustion in systems A and B respectively? System A: Adiabatic system System B: Diathermic containerMediumSingle correctHas a figure
  6. 13 Apr 2023, Shift 2 · Q68Identify the correct order of standard enthalpy of formation of sodium halides.MediumSingle correct

2022 4 questions

  1. 25 Jul 2022, Shift 1 · Q82The enthalpy of combustion of propane, graphite and dihydrogen at 298 K are −2220.0 kJ mol−1-2220.0\ \mathrm{kJ\,mol^{-1}},…EasyNumerical value
  2. 28 Jul 2022, Shift 1 · Q62Which of the following relation is not correct ?EasySingle correct
  3. 24 Jun 2022, Shift 1 · Q822O3(g)⇌3O2(g)\mathrm{2O_3(g)\rightleftharpoons 3O_2(g)} At 300 K, ozone is fifty percent dissociated. The standard free energy change at this…MediumNumerical value
  4. 29 Jun 2022, Shift 1 · Q8217.0 g of NH3\mathrm{NH_3} completely vapourises at −33.42∘C-33.42^\circ\mathrm{C} and 1 bar pressure and the enthalpy change in the process is…EasyNumerical value

2021 4 questions

  1. 3 Aug 2021, Shift 2 · Q54The work done by an ideal monoatomic gas when it is taken along the path ABCD as shown in the figure is xP0V0xP_0V_0. The value of (−x)(-x) is…HardNumerical valueHas a figure
  2. 25 Jul 2021, Shift 1 · Q55At 298 K, the enthalpy of fusion of a solid (X) is 2.8 kJ mol−1^{-1} and the enthalpy of vaporisation of the liquid (X) is 98.2 kJ…EasyNumerical value
  3. 16 Mar 2021, Shift 2 · Q54At 25∘25^\circC, 50 g of iron reacts with HCl to form FeCl2\mathrm{FeCl_2}. The evolved hydrogen gas expands against a constant pressure of 1…MediumNumerical value
  4. 18 Mar 2021, Shift 1 · Q53For the reaction C2H6→C2H4+H2\mathrm{C_2H_6 \rightarrow C_2H_4 + H_2} the reaction enthalpy ΔrH=\Delta_rH = __________ kJ mol−1^{-1}. (Round off to…EasyNumerical value

2020 3 questions

  1. 8 Jan 2020, Shift 1 · Q47The magnitude of work done by a gas that undergoes a reversible expansion along the path ABC shown in the figure is ______.EasyNumerical valueHas a figure
  2. 9 Jan 2020, Shift 2 · Q26The true statement amongst the following is :EasySingle correct
  3. 2 Sep 2020, Shift 1 · Q46The internal energy change (in J) when 90 g of water undergoes complete evaporation at 100∘100^\circC is ______. (Given : ΔHvap\Delta H_{vap}…EasyNumerical value

2017 2 questions

  1. 2 Apr 2017 (offline) · Q31Given C(graphite)+O2(g)→CO2(g)\mathrm{C_{(graphite)}+O_2(g)\rightarrow CO_2(g)} ; ΔrH∘=−393.5 kJ mol−1\Delta_rH^\circ=-393.5\ \mathrm{kJ\,mol^{-1}}…EasySingle correct
  2. 2 Apr 2017 (offline) · Q33ΔU\Delta U is equal to :EasySingle correct

Pattern: Asked most years.