1 / 76

Properties of Gases: Pressure, Volume, and Temperature Laws

This chapter explores the properties of gases, including pressure, volume, and temperature laws such as Boyle's Law, Charles' Law, Gay-Lussac's Law, and Avogadro's Law. It also discusses the behavior of ideal and real gases and introduces the Ideal Gas Equation.

mcdonaldp
Download Presentation

Properties of Gases: Pressure, Volume, and Temperature Laws

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 12 Properties Of Gases

  2. Pressure Measure of the number of collisions between gas particles and a unit area of the wall of the containerPressure = force / unit area

  3. Force/area English system: pounds/in2 (psi) Metric system: Newton/m2 (pascal)

  4. Torricelli Barometer h = 760 mm Hg 1 atmosphere pressure

  5. 1 atm = 760 torr (mm Hg) = 101.325 kPa = 1.01325 bar =14.70 psi

  6. Patm Manometer h Pgas

  7. Patm Manometer h Pgas

  8. Volume Total space of a container that gases occupy due to the free random motion of the gas molecules

  9. Relationship between Volume & Pressure of Gases P-V

  10. V P (at constant T)

  11. Slope = k V 1/P (at constant T)

  12. In mathematical terms: y = mx + b Boyle’s Law

  13. Relationship between Volume & Temperature of Gases V-T

  14. In mathematical terms: y = mx + b V = mT + b Charles’ Law

  15. Where T must be in Kelvin (K) temperature K = 0C + 273

  16. Relationship between Pressure & Temperature of Gases P-T

  17. In mathematical terms: y = mx + b P = mT + b Gay-Lussac’s Law

  18. Relationship between Volume & Moles of Gases V-n

  19. In mathematical terms: y = mx + b V = mn + b Avogadro’s Law

  20. Avogadro’s Hypothesis At constant temperature and pressure, equal volumes of gases contain equal number of particles

  21. Combined Gas Law

  22. Ideal & Real Gasses

  23. Kinetic Molecular Theory 1. Gases consist of small particles that are far apart in comparison to their own size. These particles are considered to be tiny points occupying a negligible volume compared to that of their container.

  24. Kinetic Molecular Theory 2. Molecules are in rapid and random straight-line motion. This motion can be described by well-defined and established laws of motion.

  25. Kinetic Molecular Theory 3. The collisions of molecules with the walls of a container or with other molecules are perfectly elastic. That is, no loss of energy occurs.

  26. Kinetic Molecular Theory 4. There are no attractive forces between molecules or between molecules and the walls with which they collide.

  27. Kinetic Molecular Theory 5. At any particular instant, the molecules in a given sample of gas do not all possess the same amount of energy.

  28. Ideal Gas Equation

  29. Note that is similar to the Combined Gas Law derived earlier.

  30. Variations on Ideal Gas Equation

  31. Bromine Variations on Ideal Gas Equation

  32. Real Gas Behavior

  33. Ideal Gas Equation P V = n R T

  34. N2 2.0 CH4 H2 PV nRT 1.0 Ideal gas CO2 0 0 200 400 600 800 1000 P (atm)

  35. “correct” for volume of molecules (V - b)

  36. also “correct” for attractive forces between molecules

  37. van der Waals’ Equation for 1 mole

  38. van der Waals’ Equation for n moles

  39. from CRC Handbook a*b* He 0.03412 0.02370 Ne 0.2107 0.01709 *when P(atm) & V(L)

  40. from CRC Handbook a*b* NH3 4.170 0.03707 H2O 5.464 0.03049 *when P(atm) & V(L)

  41. from CRC Handbook a*b* CCl4 20.39 0.1383 C5H12 19.01 0.1460 *when P(atm) & V(L)

  42. Cl2 gas has a = 6.49, b = 0.0562 • For 8.0 mol Cl2 in a 4.0 L tank at 27oC. • P (ideal) = nRT/V = 49.3 atm • P (van der Waals) = 29.5 atm

  43. T & P conditions where a real gas approximates an ideal gas?

  44. 203 K N2 gas 293 K 1.8 1.4 673 K PV nRT Ideal gas 1.0 0.6 0 200 400 600 800 P (atm)

  45. T & P conditions where a real gas approximates an ideal gas? high temperature low pressure

  46. Gaseous Molecular Movement

  47. Partial Pressure pressure exerted by each component in a mixture of gases

More Related