2. In order to compare two gases, we choose a standard temperature and pressure: STP: standard temperature and pressure → 273.15 K and 101 kPa → one mole of gas has a volume of 22.4 L SATP: standard ambient temperature and pressure → 298.15 K and 100 kPa → one mole of gas has a volume of 24.8 L

3. gases exert a pressure on the walls of their container. P F (N) A (m 2 )  SI unit: 1 N/m 2 = 1 Pascal (Pa) pressure is defined as force per unit area:

5. The atmospheric pressure can be measured using a barometer.

6. 760 mm Hg = 1 atm= 101 kPa Standard atmospheric pressure supports a column of mercury about 760 mm high.

8. If the barometer reads 753.3 mm Hg, what is the atmospheric pressure in atm and kPa? = 0.9912 atm 753.3 mm Hg 760 mm Hg 1 atm = 100.4 kPa 101.325 kPa 753.3 mm Hg 760 mm Hg

9. Pressure Conversions: 1. 0.875 atm to mmHg 2. 745.0 mmHg to atm 3. 0.955 atm to kPa 4. 98.35 kPa to atm 5. 740.0 mmHg to kPa 6. 99.25 kPa to mmHg Temperature Conversions: 1. 250 Kelvin to Celsius 2. 339 Kelvin to Celsius 3. 17 Celsius to Kelvin 4. 55 Celsius to Kelvin 5. -200 Celsius to Kelvin 665 mm Hg 0.9803 atm 96.8 kPa 0.9706 atm 98.65 kPa 744.4 mm Hg

10. ► Practice, p.150 #1 - 4

12. Graph the following information Pressure (KPa) Volume (L) 1005.00 1104.55 1204.16 1303.85 1403.57 K (VP) 500 500.5 499.2 500.5 499.8 P 1 V 1 = K = P 2 V 2 Is there a relationship between pressure and volume? volume pressure

14. For a given mass of gas at constant temperature, the volume of a gas varies inversely with pressure. P 1 V 1 = P 2 V 2

15. ► Practice, p.152 #5 - 10

16. Graph the following data Temperature (K)Volume (L) 298 5.00 323 5.42 348 5.84 373 6.26 398 6.68 K (V/T) 0.0167 0.0168 V 1 /T 1 = K = V 2 /T 2 temperature volume Is there a relationship between pressure and volume?

18. V versus T for different gases

19. Charles discovered that volume is directly proportional to its Kelvin temperature if a fixed mass remains under constant pressure. V 1 V 2 T 1 T 2 =

20. ► Practice, p.154 #11 - 13 ► Practice, p.156 #14 - 18

21. V 1 P 1 = V 2 P 2 T 1 T 2

22. ► Practice, p.159 #20 – 23,25-26 ► Section 4.1 Questions #1 – 7, 9a, 10 - 12