Class 11 – Chemistry – Thermodynamics Test

Time: 30 minutes Marks - 15

1. Which of the following are state functions:

Work, heat, enthalpy, volume, temperature, pressure, entropy (1m)

2. State the first law of thermodynamics for an isothermal process involving expansion of an ideal

gas. (1 m)

3. What is meant by the reference form of an element? What is the standard enthalpy of

formation of an element in its reference form? (2 m)

4. What do you understand by Gibb’s energy or Gibb’s free energy? What are its units? (2 m)

5. Determine the enthalpy of reaction for the hydrogenation of acetylene to form ethane: (3 m)

6. Use standard enthalpies of formation to calculate the value of ArH

0 for the reaction (2 m)

7. Calculate the bond energy of H—Cl Given: (2 m)

8. The enthalpy of vapourisation of benzene (C6H6) is 30.8 kJ/mol at its boiling point 80°C. Calculate

the entropy change in going from (i) liquid to vapour and (ii) vapour to liquid at 80°C. (2 m)