Thermodynamics & Thermochemistry — NEET Practice

Q: What causes most Thermodynamics mistakes?

Sign conventions for heat and work, confusing state functions with path functions, and using inconsistent units are common sources of error.

Q: What does negative ΔG indicate?

For a process under the stated conditions, negative Gibbs free-energy change indicates thermodynamic spontaneity.

Q: How should I revise Thermodynamics?

Build a one-page sign-convention and formula sheet, then practise problems that require choosing the correct relation rather than only substituting numbers.

Practice Thermodynamics and Thermochemistry MCQs for NEET with stepwise solutions, conceptual tips, chapter summary and ChemNexa mock tests.

Thermodynamics and Thermochemistry Revision Guide for NEET Chemistry

Thermodynamics relates heat, work, internal energy, enthalpy and spontaneity. It is best learned through sign conventions and state-function logic rather than isolated memorisation.

For NEET Chemistry, revise the first law, enthalpy changes, Hess law, entropy and Gibbs free energy, then practise conceptual and numerical MCQs together.

Important Topics

System, surroundings and state functions
First law of thermodynamics
Enthalpy and heat capacity
Hess law
Entropy
Gibbs free energy and spontaneity

Important Formulae & Relationships

ΔU = q + w
At constant pressure: qp = ΔH
ΔH = ΔU + ΔngRT (for ideal-gas reactions)
ΔG = ΔH − TΔS
ΔG° = −RT ln K

Use formulas only after checking the required units, sign convention and assumptions for the question.

What to practise in Thermodynamics and Thermochemistry

Concept Revision

Revise definitions, principles, equations, trends and core ideas from Thermodynamics and Thermochemistry before attempting MCQs.

Exam-style MCQs

Use chapter-focused multiple-choice practice to improve accuracy, recall and application for NEET Chemistry.

Performance Practice

Attempt ChemNexa tests, review results and return to weak areas for another round of targeted revision.

Top 5 Thermodynamics and Thermochemistry MCQs with Answers

These public questions are selected from the exact Thermodynamics and Thermochemistry chapter, screened for topic relevance and deduplicated so repeated versions of the same MCQ are not shown publicly. Use them for quick revision, then sign in to attempt the complete test experience with more questions, results and performance review.

NEET Chemistry · Thermodynamics and Thermochemistry · Very Very Hard

1. For spontaneous process at constant T,P:

A. ΔH=0
B. ΔG=0 always
C. ΔG<0
D. ΔG>0

Answer: C

Explanation: Negative Gibbs energy change indicates spontaneity.

NEET Chemistry · Thermodynamics and Thermochemistry · Very Very Hard

2. At constant pressure, heat absorbed equals:

A. ΔU always
B. ΔH
C. ΔV
D. ΔS

Answer: B

Explanation: For PV work, qp=ΔH.

NEET Chemistry · Thermodynamics and Thermochemistry · Very Very Hard

3. For an exothermic process, ΔH is:

A. Infinite
B. Positive
C. Zero
D. Negative

Answer: D

Explanation: Heat is released, so ΔH<0.

NEET Chemistry · Thermodynamics and Thermochemistry · Very Very Hard

4. For ideal-gas isothermal process, ΔU is:

A. Zero
B. Negative
C. Always q
D. Positive

Answer: A

Explanation: Ideal-gas U depends only on temperature.

NEET Chemistry · Thermodynamics and Thermochemistry · Very Very Hard

5. Relation between ΔG° and K is:

A. ΔG°=-RT lnK
B. ΔG°=-KRT
C. ΔG°=RT lnK
D. ΔG°=RT/K

Answer: A

Explanation: Standard relation is ΔG°=-RTlnK.