CN  ChemNexa

Thermodynamics JENPAS MCQ & Practice Questions

Practice Thermodynamics MCQs for JENPAS Chemistry with answers, explanations, chapter revision and related ChemNexa mock tests.

Register Free for Full Chemistry Practice

Thermodynamics Revision Guide for JENPAS 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 JENPAS 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

Concept Revision

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

Exam-style MCQs

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

Performance Practice

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

Top 20 Thermodynamics MCQs with Answers

These public questions are selected from the exact Thermodynamics 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.

JENPAS Chemistry · Thermodynamics · Very Very Hard

1. Consider: (I) ΔU=q+w; (II) qp=ΔH at constant pressure; (III) ΔG<0 favours spontaneity at constant T,P; (IV) Cp-Cv=R for an ideal gas. Which are correct?

  • A. I, III and IV only
  • B. I, II, III and IV
  • C. I and II only
  • D. II and III only
Answer: B
Explanation: All four statements are standard thermodynamic relations.

JENPAS Chemistry · Thermodynamics · Very Very Hard

2. JENPAS advanced: Consider: (I) ΔU=q+w; (II) qp=ΔH at constant pressure; (III) ΔG<0 favours spontaneity at constant T,P; (IV) Cp-Cv=R for an ideal gas. Which are correct?

  • A. I and II only
  • B. II and III only
  • C. I, III and IV only
  • D. I, II, III and IV
Answer: D
Explanation: All four statements are standard thermodynamic relations.

JENPAS Chemistry · Thermodynamics · Very Very Hard

3. The first law of thermodynamics is commonly written as:

  • A. ΔU = q/w
  • B. ΔU = 0 for every process
  • C. ΔU = q + w
  • D. ΔU = q - w always
Answer: C
Explanation: Using the chemistry sign convention, change in internal energy equals heat supplied plus work done on the system.

JENPAS Chemistry · Thermodynamics · Very Very Hard

4. Which is a state function?

  • A. Path length
  • B. Internal energy
  • C. Heat
  • D. Work
Answer: B
Explanation: Internal energy depends only on state, whereas heat and work are path functions.

JENPAS Chemistry · Thermodynamics · Very Very Hard

5. For an ideal gas in an isothermal process, ΔU is:

  • A. Negative
  • B. Always equal to q
  • C. Zero
  • D. Positive
Answer: C
Explanation: Temperature is constant, so internal energy does not change.

JENPAS Chemistry · Thermodynamics · Very Very Hard

6. At constant temperature and pressure, spontaneity requires:

  • A. ΔG < 0
  • B. ΔG > 0
  • C. ΔG = 0 always
  • D. ΔH = 0
Answer: A
Explanation: Negative Gibbs energy change indicates spontaneous direction.

JENPAS Chemistry · Thermodynamics · Very Very Hard

7. A process with ΔH<0 and ΔS>0 is:

  • A. Non-spontaneous at all temperatures
  • B. Spontaneous only at high T
  • C. Spontaneous only at low T
  • D. Spontaneous at all temperatures
Answer: D
Explanation: Both terms favour ΔG<0 at every temperature.

JENPAS Chemistry · Thermodynamics · Very Very Hard

8. A process with ΔH>0 and ΔS<0 is:

  • A. Spontaneous only at high T
  • B. Spontaneous only at low T
  • C. Non-spontaneous at all temperatures
  • D. Spontaneous at all temperatures
Answer: C
Explanation: Both terms make ΔG positive.

JENPAS Chemistry · Thermodynamics · Very Very Hard

9. A process with ΔH<0 and ΔS<0 tends to be spontaneous at:

  • A. No temperature
  • B. Low temperature
  • C. High temperature
  • D. All temperatures
Answer: B
Explanation: At low T the favourable negative ΔH can dominate.

JENPAS Chemistry · Thermodynamics · Very Very Hard

10. A process with ΔH>0 and ΔS>0 tends to be spontaneous at:

  • A. High temperature
  • B. Low temperature
  • C. All temperatures
  • D. No temperature
Answer: A
Explanation: At high T, the favourable -TΔS term can dominate.

JENPAS Chemistry · Thermodynamics · Very Very Hard

11. JENPAS advanced: The first law of thermodynamics is commonly written as:

  • A. ΔU = q + w
  • B. ΔU = q - w always
  • C. ΔU = q/w
  • D. ΔU = 0 for every process
Answer: A
Explanation: Using the chemistry sign convention, change in internal energy equals heat supplied plus work done on the system.

JENPAS Chemistry · Thermodynamics · Very Very Hard

12. JENPAS advanced: Which is a state function?

  • A. Heat
  • B. Work
  • C. Path length
  • D. Internal energy
Answer: D
Explanation: Internal energy depends only on state, whereas heat and work are path functions.

JENPAS Chemistry · Thermodynamics · Very Very Hard

13. JENPAS advanced: For an ideal gas in an isothermal process, ΔU is:

  • A. Zero
  • B. Positive
  • C. Negative
  • D. Always equal to q
Answer: A
Explanation: Temperature is constant, so internal energy does not change.

JENPAS Chemistry · Thermodynamics · Very Very Hard

14. JENPAS advanced: At constant temperature and pressure, spontaneity requires:

  • A. ΔG = 0 always
  • B. ΔH = 0
  • C. ΔG < 0
  • D. ΔG > 0
Answer: C
Explanation: Negative Gibbs energy change indicates spontaneous direction.

JENPAS Chemistry · Thermodynamics · Very Very Hard

15. JENPAS advanced: A process with ΔH<0 and ΔS>0 is:

  • A. Spontaneous only at low T
  • B. Spontaneous at all temperatures
  • C. Non-spontaneous at all temperatures
  • D. Spontaneous only at high T
Answer: B
Explanation: Both terms favour ΔG<0 at every temperature.

JENPAS Chemistry · Thermodynamics · Very Very Hard

16. JENPAS advanced: A process with ΔH>0 and ΔS<0 is:

  • A. Non-spontaneous at all temperatures
  • B. Spontaneous at all temperatures
  • C. Spontaneous only at high T
  • D. Spontaneous only at low T
Answer: A
Explanation: Both terms make ΔG positive.

JENPAS Chemistry · Thermodynamics · Very Very Hard

17. JENPAS advanced: A process with ΔH<0 and ΔS<0 tends to be spontaneous at:

  • A. High temperature
  • B. All temperatures
  • C. No temperature
  • D. Low temperature
Answer: D
Explanation: At low T the favourable negative ΔH can dominate.

JENPAS Chemistry · Thermodynamics · Very Very Hard

18. JENPAS advanced: A process with ΔH>0 and ΔS>0 tends to be spontaneous at:

  • A. All temperatures
  • B. No temperature
  • C. High temperature
  • D. Low temperature
Answer: C
Explanation: At high T, the favourable -TΔS term can dominate.

JENPAS Chemistry · Thermodynamics · Very Very Hard

19. Thermodynamic reasoning: The first law of thermodynamics is commonly written as:

  • A. ΔU = q/w
  • B. ΔU = 0 for every process
  • C. ΔU = q + w
  • D. ΔU = q - w always
Answer: C
Explanation: Using the chemistry sign convention, change in internal energy equals heat supplied plus work done on the system.

JENPAS Chemistry · Thermodynamics · Very Very Hard

20. Thermodynamic reasoning: Which is a state function?

  • A. Path length
  • B. Internal energy
  • C. Heat
  • D. Work
Answer: B
Explanation: Internal energy depends only on state, whereas heat and work are path functions.

Login to Start Full Test

Thermodynamics Practice Tests

Thermodynamics Frequently Asked Questions

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.

What does negative ΔG indicate?

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

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.

Continue with another chapter to build connected concepts and strengthen your overall Chemistry preparation.

Continue JENPAS Chemistry

View all JENPAS chapters and testsBrowse all Chemistry PracticeCreate a free account