CBSE Class 11 Chemistry Chemical Thermodynamics MCQs

I. MCQ - Choose Appropriate Alternative

1. The quantity of heat evolved or absorbed during a chemical reaction is called __________. (Heat or Reaction, Heat of Formation, Heat of Combination)

2. An endothermic reaction is one, which occurs __________. (With evolution of heat, With absorption of Heat, In forward Direction)

3. An exothermic reaction is one during which __________. (Heat is liberated, Heat is absorbed, no change of heat occurs)

4. The equation C + O₂ → CO₂ delta H = -408KJ represents __________ reaction. (Endothermic, Exothermic, Reversible)

5. The equation N₂ + O₂ → 2NO ΔH = 180KJ represents __________ reaction. (Endothermic, Exothermic, Irreversible)

6. Thermo-chemistry deals with __________. (Thermal Chemistry, Mechanical Energy, Potential Energy)

7. Enthalpy is __________. (Heat content, Internal energy, Potential Energy)

8. Hess’s Law is also known as __________. (Law of conservation of Mass, Law of conservation of Energy, Law of Mass Action)

9. Any thing under examination in the Laboratory is called __________. (Reactant, System, Electrolyte)

10. The environment in which the system is studied in the laboratory is called __________. (Conditions, Surroundings, State)

11. When the bonds being broken are more than those being formed in a chemical reaction, then ΔH will be __________. (Positive, Negative, Zero)

12. When the bond being formed are more than those being broken in a chemical reaction, then the ΔH will be __________. (Positive, Negative, Zero)

13. The enthalpy change when a reaction is completed in single step will be __________ as compared to that when it is completed in more than one steps. (Equal to, Partially different from, Entirely different from)

14. The enthalpy of a system is represent by __________. (H, ΔH, ΔE)

15. The factor E + PV is known as __________. (Heat content, Change in Enthalpy, Work done)

16. Heat of formation is represented by __________. (Δf, ΔHf, Hf)

17. The heat absorbed by the system at constant __________ is completely utilize to increase the internal energy of the system. (Volume, Pressure, Temperature)

18. Heat change at constant __________ from initial to final state is simply equal to the change in enthalpy. (Volume, Pressure, Temperature)

19. A system, which exchange both energy and energy with the surrounding, is __________ system. (Open, Closed, Isolated)

20. A system, which only exchange energy with the surrounding but not the matter, is __________ system. (Open, Closed, Isolated)

II. Fill in the Blank

1. The branch of Chemistry, which deals with the heat changes that take place during chemical reaction, is called __________.

2. The branch of science which deals with energy changes accompanying physical and chemical transformation is called __________.

3. The amount of heat evolved or absorbed in a chemical reaction is called __________.

4. Such reactions in which heat is evolved are called __________ reactions.

5. Such reactions in which heat is absorbed are called __________ reactions.

6. In exothermic reactions, heat evolved is given by __________ sign of DH.

7. In endothermic reactions heat absorbed is given by __________ sign of DH.

8. The total heat change in a reaction is the same whether it takes place in one or several steps.

9. The first law of thermodynamics is also known as __________.

10. The part of universe under observation is called __________.

11. The system plus its surrounding is called __________.

12. Such properties, which give description of a system at a particular moment.

13. The term E + PV is called __________.

14. DH represents change in __________.

15. The temperature of water is raised up when sulphuric acid is added to it. This is an __________ reaction.

16. The characteristic properties of a system which is independent of amount of material concerned is called __________ properties.

17. The characteristic properties of a system which depend on amount of substance present in it is called __________ properties.

18. Density, pressure and temperature are the examples of __________ properties.

19. Mole numbers and enthalpy are the examples of __________ properties.

20. A system, which exchange both energy and matter with its surrounding, is called __________ system.

21. A system, which only exchange energy with the surrounding but not matter is, called __________ system.

22. A system which neither exchange energy nor matter with its surrounding is called __________ system.

23. A system is __________ if it contains only one phase.

24. A system is __________ if it contains more than one phase.

25. 1 kilojoule is equal to __________ joules.

26. 1 Calorie is equal to __________ joules.

27. 1 kilo calorie is equal to __________ joules.

28. The work done (w) is mathematically denoted by __________.

29. The change in enthalpy is denoted by __________.

30. __________ law is used in calculating heat of reaction.

31. __________ is defined as the change in enthalpy when one gram mole of a compound is produced from its element.

32. Heat of formation is denoted by __________.

33. When the work is done on the system by the surrounding the sign of work done (w) is __________.

34. When the work is done by the system on surrounding the sign of work done is __________.

35. First law of Thermodynamics is mathematically represented as __________.

36. Standard enthalpies are measured at __________.

37. Hess’s Law is employed to calculate __________ of a chemical reaction.

38. Heat absorbed by the system at constant volume is completely utilize to increase the __________ of the system.

39. Heat change at constant pressure from initial to final state of the system is simply equal to the __________.

40. SI unit of measurement of heat change is __________.