1. Gases

2. Drill  Name the following:   1.HSO 4 -1 __________   2.OH -1 __________   3.ClO 3 -1 __________   4.C 2 H 3 O 2 -1 __________   5.OCN -1 __________

3. Drill  Name the following:   1.HSO 4 -1 bisulfate or hydrogen sulfate   2.OH -1 hydroxide   3.ClO 3 -1 chlorate   4.C 2 H 3 O 2 -1 acetate   5.OCN -1 cyanate

4. Objectives  iWBAT  Calculate the partial pressure of a gas  List, and distinguish between, each postulate of the KMT  Explain the difference between a “real” and “ideal” gas.  Solve collecting gas over water calculations

5. Partial Pressure Video  http://youtu.be/pgTTKYhqQY0

6. Partial Pressure  A balloon contains 0.2 moles of nitrogen and 0.5 moles of oxygen. If the total pressure in the balloon is 2.0 atm, what is the partial pressure of oxygen?

7. Partial Pressure  P x = P Total ( n x / n Total )P x = 2.0 atm (0.5 moles/0.7 moles) = 1.4 atm

8. Collect Gas over Water  http://youtu.be/E5NBZgQ5cl0

9. Collect Gas Over Water  193 mL of O 2 was collected over water on a day when the atmospheric pressure was 762 mmHg. The temperature of the water was 23.0 o C. How many grams of oxygen were collected?

10.  Use Dalton's law and the vapor pressure of water at 23.0 o C to correct the pressure to units of atmospheres. PT = P oxygen +P water Convert the corrected pressure to atmospheres. Use the ideal gas law to find out how many moles of gas were produced: PV = nRT Use the number of moles and the molecular weight of oxygen to find out how many grams of oxygen were collected.

11. Kinetic Molecular Theory  http://youtu.be/D2-DtoSQ1Rc

12. Kinetic Molecular Theory For IDEAL GASES 1. Volume of individual particles is  zero. 2.Collisions of particles with container walls cause pressure exerted by gas. 3.Particles exert no forces on each other. 4.Average kinetic energy  Kelvin temperature of a gas.

13. The Meaning of Temperature Kelvin temperature is an index of the random motions of gas particles of a gas (higher T means greater motion.)

14. Real Gases vs Ideal Gases  http://youtu.be/0i2pfnTDEoI

15. Real Gases  Must correct ideal gas behavior when at high pressure (smaller volume) and low temperature (attractive forces become important).

16. Figure 5.28 Volume Taken up by Gas Particles

17. Real Gases corrected pressure corrected volume P ideal V ideal

18. Problems to Try  (8 th edition) 7,9,13,17,20, 22, 23, 24, 27, 29, 31, 34, 37, 41, 42, 44, 45, 48, 50, 51, 54, 59, 61, 67, 68, 71, 73, 83, 85  (10 th edition) P. 232 # 22, p. 234-235 # 62-84 even

19. Wrap Up  What are the conditions that make a gas “real”?  The van der Waals equation accounts for which differences between real and ideal gases?

20. Figure 5.24 Plots of PV/nRT Versus P for Several Gases (200 K)