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THERMODYNAMICS

Q1. Under what conditions ∆H becomes equals to ∆U?
Q2. State the thermodynamic conditions for the process to occur

spontaneously.
Q3. What is the value of ∆G and ∆S of a system at equilibrium?

Q4. Under what conditions ∆H is equal to ∆G?
Q5. What is state function? Give example.

Q6. What is the condition for adiabatic process?
Q7. What are the enthalpies of formation of all the elements in their
standard state?

Q8. Given N + 3H → 2NH , ∆ H = -92.4 KJ. What is the standard
2
r
3
2
enthalpy of formation of NH gas?
3
Q9.For the reaction 2Cl → Cl 2(g) , what are signs of ∆H and ∆S?
(g)
Q10. For an isolated system, ∆U = 0. What will be ∆S?
Q11. What is the relation between ∆H and ∆U?
Q12. At what temperature entropy of a perfect crystalline substance is

taken as zero?
Q13. What is an adiabatic process?
st
Q14. State 1 law of thermodynamics. Write its mathematical form.
Q15. The value of ∆ H for NH is -91.8 KJ/mol. Calculate enthalpy
3
f
change for the following reaction: 2NH → N + 3H 2
3
2
Q16. State Hess’s law.
Q17. What are extensive properties? Give example.

Q18. What are intensive properties? Give example.
Q19. What is reversible process?

Q20. Define enthalpy of formation?
Q21. The enthalpy of combustion of carbon to CO is -393.5 KJ/mol.
2
Q22. The combustion of 1 mole of benzene takes place at 298 K and 1

atm pressure. After combustion CO2 and H2O are produced and 3267
KJ of energy is released. Calculate standard enthalpy of formation of