Thermodynamics Mock Test – Class 11 Chemistry

1. The standard enthalpy of formation of an element in its most stable standard state is taken as

2. The table gives bond-count information for a reaction.

The row with the incorrect interpretation is

3. Read the case below and identify the correct system classification.

4. A gas sample is heated by once at constant volume and once at constant pressure. The same amount is used in both trials. For an ideal gas, the heat required at constant pressure is greater by

5. A claim says, “Specific heat capacity and molar heat capacity have the same unit because both measure heat needed for temperature rise.” The best correction is that

6. The value of for a reaction is most directly a measure of

7. The entropy change for a reversible heat transfer at temperature is given by

8. For the reaction , and as written. The reaction is first reversed and then divided by . At , the for the final written reaction is closest to

9. A heat capacity value tells how much heat is required to raise the temperature of an object by

10. For an ionic solid , the data are , , , , and . The hydration enthalpies of and are and . The enthalpy of solution is closest to

11. The equation that correctly represents the standard enthalpy of formation of is

12. A gas is heated in a rigid sealed container. The pressure rises, but the volume remains fixed. The process is best described as

13. A uniform gas sample at is split into two equal containers without changing the temperature of either part. Which set contains properties that would be expected to reduce to half for each part?

14. A compression process has , , and . During the same process, the system releases heat. Use . The internal energy change is

15. The SI unit of energy used in thermodynamics is

16. A learner says, “Because has the unit , it must be a state function just like .” The reasoning fails because

17. A student compares two constant-pressure reactions:

The correct comparison is

18. A liquid vaporizes reversibly at its boiling point. If and , the entropy of vaporization is

19. A system releases of heat but has of work done on it. The system's internal energy

20. A gas undergoes free expansion in an insulated container. For this process, and . The first law then gives

21. A reaction has and . At , the reaction mixture has . Use and . The actual is closest to

22. For a thermodynamic system, the absolute value of internal energy is generally not measured directly. What is normally measured and used is

23. A sample of water is divided into two equal parts. The temperature of each part remains , but the mass of each part becomes half of the original. This observation shows that

24. A reaction at has , , and . Use and . The actual Gibbs energy change is closest to

25. A student says, “A salt can dissolve only if its enthalpy of solution is negative.” The best correction is that

26. For an ideal gas, is larger than mainly because at constant pressure

27. One mole of an ideal gas expands reversibly and isothermally at from to . Use and . For the gas, the values of , , and are closest to

28. A reaction mixture has for the forward reaction at its current composition. The reverse reaction under the same conditions has

29. An ideal gas expands reversibly and isothermally from to . The work is proportional to

30. A neutralization reaction is carried out in a coffee-cup calorimeter. of acid and of base are mixed, and of water is formed. The total solution mass is , , and the temperature rises by . Neglecting the cup heat capacity, the enthalpy of neutralization per mole of water formed is

31. A system loses of heat reversibly at . The entropy change of the system is

32. A table lists possible standard formation equations.

The rows that represent standard enthalpy of formation equations are

33. A route map shows three paths from the same initial state to the same final state:
Path P: slow heating followed by expansion
Path Q: expansion followed by heating
Path R: a single combined heating-expansion step
For the internal energy change, the best conclusion is

34. In an insulated calorimetry setup, the basic heat balance is that

35. Assertion: In a cyclic process, if the system returns to the same thermodynamic state.
Reason: Enthalpy is a state function.

36. A gas expands from to in two ways.
Case 1: against external pressure.
Case 2: into vacuum.
Use . The work values for Case 1 and Case 2 are

37. A solid sample melts at its melting point to form a liquid. The entropy change of the sample is best linked with

38. A process is described as adiabatic. The statement that must be true for the system is

39. A reaction has and . At , is

40. A graph has on the horizontal axis and on the vertical axis. Three constant-pressure expansion lines go from the same to the same :
Line P at
Line Q at
Line R at
The expansion with the greatest work magnitude is

41. For a gaseous reaction at , , , and . Use . The approximate is

42. Thermodynamics mainly deals with the study of changes involving heat, work, energy, and matter. In chemistry, its use is most directly seen when we study

43. A system changes from state P to state Q by two different routes. If the initial and final states are identical in both routes, the value of will

44. For a reaction with and , the temperature at which is

45. At constant volume, the first law becomes

46. A final thermodynamic check for spontaneity at constant and should use

47. For the reaction , the sign of is expected to be

48. A gaseous reaction has , , and at . Use . The standard Gibbs energy change is closest to

49. A process has , but it appears very slow at room temperature. The best conclusion is that

50. A reaction has and . The reaction is non-spontaneous at but spontaneous at . This observation is consistent because