6. Gaseous State

2 & 3 Marks

1. Define Pressure.

2. Define pascal.

3. Give the relation with the commonly used Units of pressure and SI unit.

4. State Boyle's law.

5. Give the mathematical form of Boyle’s law. Or Write the mathematical statement of Boyle’s law.

6. Derive the pressure-density relationship from the Boyle’s law.

7. Explain - The size of a weather balloon becomes larger and larger as it ascends up into larger altitude.

8. State Charles Law.

9. Give the mathematical equation of Charles Law. Or Write the mathematical statement of Charles Law.

10. How a balloon moved from an ice cold water bath to a boiling water bath can be used as a model for Charle’s law?

11. How a balloon filled with air at room temperature and cooled to a much lower temperature can be used as a model for Charle’s law?

12. State Gay-Lussac’s Law.

13. Give the mathematical form of Gay-Lussac’s Law.

14. Name two items that can serve as a model for Gay Lussac’s law and explain.

15. Explain - The tyre of an automobile is inflated to slightly lesser pressure in summer than in winter.

16. Explain - Aerated water bottles are kept under water during summer.

17. Explain - Liquid Ammonia bottle is cooled before opening the seal.

18. Aerosol cans carry clear warning of heating of the can. Why?

19. State Avogadro’s Hypothesis.

20. Give the mathematical form of Avogadro’s Hypothesis.

21. Give the mathematical expression that relates gas volume and moles. Describe in words what the mathematical expression means.

22. Derive Ideal gas equation.

23. What are Ideal gases? In what way Real gases differ from Ideal gases?

24. Give the values of Gas constant R in different units.

25. State Dalton’s law of partial pressures.

26. Mention the Application of Dalton’s law.

27. Suggest why there is no Hydrogen (H2) in our atmosphere. Why does the moon have no atmosphere?

28. Define Graham's law of Diffusion. Or Define Graham's law of Effusion.

29. Give the mathematical form of Graham's law of diffusion or effusion.

30. Distinguish between diffusion and effusion.

31. When Ammonia combines with HCl, NH4Cl is formed as white dense fumes. Why do more fumes appear near HCl?

32. Give suitable explanation for the following facts about gases.

      a) Gases don’t settle at the bottom of a container

      b) Gases diffuse through all the space available to them

33. When will gases deviate from ideal behavior?

34. When will gases move toward ideal behavior?

35. Define Compressibility factor.

36. Give the mathematical form of Compressibility factor.

37. What is Boyle temperature? Or What is Boyle point?

38. Write a note on Compressibility factor for real gases.

39. Suppose there is a tiny sticky area on the wall of a container of gas. Molecules hitting this area stick there permanently. Is the pressure greater or less than on the ordinary area of walls?

40. Explain whether a gas approaches ideal behavior or deviates from ideal behaviour if

      a) it is compressed to a smaller volume at constant temperature.

      b) the temperature is raised at while keeping the volume constant.

      c) more gas is introduced into the same volume and at the same temperature.

41. Which of the following gases would you expect to deviate from ideal behaviour under conditions of low temperature F2, Cl2 or Br2? Explain.

42. Can a Van der Waals gas with a = 0 be liquefied? Explain.

43. Give the mathematical expressions that relate Critical constants and Van der Waals constants.

44. Define Critical temperature (Tc).

45. Define Critical pressure (Pc).

46. Define Critical volume (Vc).

47. Explain Critical phenomena.

48. What is Joule - Thomson effect? What is its use?

49. What is Inversion temperature (Ti)?

50. Give the value of Inversion temperature (Ti) using van der waals constants a and b.

51. Critical temperature of H2O, NH3 and CO2 are 647.4, 405.5 and 304.2 K respectively. When we start cooling from a temperature of 700 K which will liquefy first and which will liquefy finally?

52. Describe Liquefaction of gases.

53. What are the conditions for Liquefaction of gases?

54. Mention / Give the different methods used for Liquefaction of gases.

55. When the driver of an automobile applies brake, the passengers are pushed toward the front of the car but a helium balloon is pushed toward back of the car. Upon forward acceleration the passengers are pushed toward the front of the car. Why?

56. Would it be easier to drink water with a straw on the top of Mount Everest?

57. Why do astronauts have to wear protective suits when they are on the surface of moon?

      Problems Boyle's law, Charles Law, Gay-Lussac’s Law, Avogadro’s Hypothesis, Ideal gas equation, Dalton’s law, Graham's law, Critical constants, Van der Waals constants

5 Marks

1. Explain Compressibility factor (Z).

2. Write the Van der Waals equation for a real gas. Explain the correction term for pressure and volume.

3. Write a note on Pressure Correction in the ideal gas equation.

4. Write a note on Volume Correction in the ideal gas equation.

5. Explain Andrew's isotherms of Carbon dioxide.

6. Derive critical constants in terms of van der Walls constants. Or

    Derive the values of van der Waals equation constants in terms of critical constants.