Choose the correct statement for the work done in the expansion and heat absorbed or released when 5 litres of an ideal gas at 10 atmospheric pressure isothermally expands into vacuum until volume is 15 litres:

Work done will be zero and heat will also be zero

Both the heat and work done will be greater than zero

Heat absorbed will be less than zero and work done will be positive

Work done will be greater than zero and heat will remain zero

Which amongst the following options is the correct relation between change in enthalpy and change in internal energy?

$$\Delta \mathrm{H}=\Delta \mathrm{U}+\Delta \mathrm{n_g R T}$$

$$\Delta \mathrm{H}-\Delta \mathrm{U}=-\Delta \mathrm{nRT}$$

$$\Delta \mathrm{H}+\Delta \mathrm{U}=\Delta \mathrm{nR}$$

$$\Delta \mathrm{H}=\Delta \mathrm{U}-\Delta \mathrm{n_g R T}$$

For irreversible expansion of an ideal gas under isothermal condition, the correct option is :

$$\Delta$$U = 0, $$\Delta$$Stotal $$\ne$$ 0

$$\Delta$$U $$\ne$$ 0, $$\Delta$$Stotal = 0

$$\Delta U = 0, $$\Delta S_{total} = 0

$$\Delta$$U $$\ne$$ 0, $$\Delta$$Stotal $$\ne$$ 0

Thermodynamics — NEET Previous Year Questions

28 solved PYQs · 2016–2026 · Chemistry

Solved PYQs: 28
Years covered: 2016–2026
Avg / year: ~3
Subject: Chemistry

How many NEET questions come from Thermodynamics?

Thermodynamics has contributed 28 questions to National Eligibility cum Entrance Test (UG) papers between 2016 and 2026 — an average of about 3 questions a year. That count is measured from EByAi’s bank of 46,150 NEET questions, not estimated from a syllabus. Every one of the 28 questions carries a written, step-by-step solution, and each is tagged to Thermodynamics within Chemistry, so you can drill this chapter across every year at once instead of hunting through paper PDFs. Practising a chapter’s full PYQ history is the fastest way to learn the patterns examiners reuse.

Sample Thermodynamics questions from real NEET papers

These are 5 real questions from the bank — exactly as asked, with the answer one tap away. All 28 Thermodynamics questions (with full written solutions) are available in practice.

Question 1 · NEET 2024
Choose the correct statement for the work done in the expansion and heat absorbed or released when
5 litres of an ideal gas at 10 atmospheric pressure isothermally expands into vacuum until volume is
15 litres:
1. (A) $Both the heat and work done will be greater than zero$
2. (B) $Heat absorbed will be less than zero and work done will be positive$
3. (C) $Work done will be zero and heat will also be zero$
4. (D) $Work done will be greater than zero and heat will remain zero$
Show answerAnswer
$Answer: (C) Work done will be zero and heat will also be zero$
Question 2 · NEET 2023
Which amongst the following options is the correct relation between change in enthalpy and change in internal energy?
1. (A) $Δ H = Δ U + Δ n_{g} RT$
2. (B) $Δ H - Δ U = - Δ nRT$
3. (C) $Δ H + Δ U = Δ nR$
4. (D) $Δ H = Δ U - Δ n_{g} RT$
Show answerAnswer
$Answer: (A) Δ H = Δ U + Δ n_{g} RT$
Question 3 · NEET 2022
A vessel contains 3.2 g of dioxygen gas at STP (273.15 K and 1 atm pressure). The gas is now transferred to another vessel at constant temperature, where pressure becomes one third of the original pressure. The volume of new vessel in L is : (Given : molar volume at STP is 22.4 L)
1. (A) $67.2$
2. (B) $6.72$
3. (C) $2.24$
4. (D) $22.4$
Show answerAnswer
$Answer: (B) 6.72$
Question 4 · NEET 2021
For irreversible expansion of an ideal gas under isothermal condition, the correct option is :
1. (A) $Δ U \neq = 0, Δ Stotal = 0$
2. (B) $Δ U = 0, Δ S_{t o t a l} = 0$
3. (C) $Δ U \neq = 0, Δ Stotal \neq = 0$
4. (D) $Δ U = 0, Δ Stotal \neq = 0$
Show answerAnswer
$Answer: (D) Δ U = 0, Δ Stotal \neq = 0$
Question 5 · NEET 2021
Which one among the following is the correct option for right relationship between CP and CV for one mole of ideal gas?
1. (A) $CV = R + CP$
2. (B) $CP + CV = R$
3. (C) $CP - CV = R$
4. (D) $CP = RCV$
Show answerAnswer
$Answer: (C) CP - CV = R$

Thermodynamics questions by year

Year	Questions	Share of chapter questions
2026	2
2025	2
2024	6
2023	3
2022	3
2021	2
2020	3
2019	2
2018	1
2017	2
2016	2

Practise these 28 questions with solutions

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FAQs

How many NEET questions have been asked from Thermodynamics?

EByAi's bank holds 28 real NEET questions from Thermodynamics, asked between 2016 and 2026 — about 3 per year on average. Every count is measured from actual papers, not estimated.

Is Thermodynamics important for NEET?

28 questions over 11 papers make Thermodynamics a steady-weightage chapter in NEET Chemistry. The year-wise table above shows exactly how often it appears.

Can I solve Thermodynamics PYQs online for free?

Yes. EByAi lets you solve NEET past-year questions in the browser with written solutions — free daily practice, no card needed.

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