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7. Gases Part B: Gas Laws Dr. Chu River Dell Regional High School

8. The barometer was invented by Evangelisto Torricelli in 1643. Barometer The temperature scale

9. Websites: http://phet.colorado.edu/en/simulation/gas- properties http://www.mhhe.com/physsci/chemistry/ess entialchemistry/flash/gasesv6.swf

10. Conditions: given amount of gas at constant temperature Relationship: PV = constant

11. A sample of gas in a balloon is compressed from 7.00 L to 3.50 L. The pressure at 7.00L is 125 KPa. What will the pressure be at 2.50L if the temperature remains constant?

12. Conditions: given amount of gas at constant pressure Relationship: V/T = constant

13. A gas sample at 20.0 C occupies a volume of 3.00 L. If the temperature is raised to 50.0 C, what will the volume be if the pressure remains constant?

14. Conditions: given amount of gas at constant volume Relationship: P/T = constant

15. The pressure of a gas in a tank is 4.00 atm at 200.0 C. If the temperature rises to 280.0 C, what will be the pressure of the gas in the tank?

16. Combination of Boyles, Charles, and Gay- Lussacs Laws. Relationship: PV/T = constant

17. A gas at 70.0KPa and 10.0 C fills a flexible container with an initial volume of 4.00L. If the temperature is raised to 60 C and the pressure is raised to 80.0 KPa, what is the new volume?

18. Carefully read the problem and list all the known and unknown parameters. Use the 1 and 2 for designations of start and end states, respectively. Carefully label each parameter with 1 or 2 subscript to keep track. If any of the three parameter is held constant, that parameter would have the same value for both states 1 and 2. Then the identical parameter can be cancelled from the combined gas law and individual gas laws reconstitute.

19. Submarines need to be extremely strong to withstand the extremely high pressure of water pushing down on them. An experimental research submarine with a volume of 15,000 liters has an internal pressure of 1.2 atm. If the pressure of the ocean breaks the submarine forming a bubble with a pressure of 250 atm pushing on it, how big will that bubble be?

20. A gas that has a volume of 28 liters, a temperature of 45 0 C, and an unknown pressure has its volume increased to 34 liters and its temperature decreased to 35 0 C. If I measure the pressure after the change to be 2.0 atm, what was the original pressure of the gas?

21. 1. A gas takes up a volume of 17 liters, has a pressure of 2.3 atm, and a temperature of 299 K. If I raise the temperature to 350 K and lower the pressure to 1.5 atm, what is the new volume of the gas? 2. A gas has a temperature of 14 0 C, and a volume of 4.5 liters. If the temperature is raised to 29 0 C and the pressure is not changed, what is the new volume of the gas? 3. If I have 21 liters of gas held at a pressure of 78 atm and a temperature of 900 K, what will be the volume of the gas if I decrease the pressure to 45 atm and decrease the temperature to 750 K?

22. 1. A gas takes up a volume of 17 liters, has a pressure of 2.3 atm, and a temperature of 299 K. If I raise the temperature to 350 K and lower the pressure to 1.5 atm, what is the new volume of the gas? [30.5L] 2. A gas has a temperature of 14 0 C, and a volume of 4.5 liters. If the temperature is raised to 29 0 C and the pressure is not changed, what is the new volume of the gas? [4.74L] 3. If I have 21 liters of gas held at a pressure of 78 atm and a temperature of 900 K, what will be the volume of the gas if I decrease the pressure to 45 atm and decrease the temperature to 750 K? [30.3L]