Unit 11: Gas Laws Section 1: Gas Pressure

What is Pressure? To create the most pressure, Ms. Stark should wear which shoes? P = F A Gas pressure is caused by _________ with the _____ of the container. Like density collisions P = F A P = F A walls

Atmospheric Pressure: weight of air per area empty space (a vacuum) weight of Hg h 760 mm Atmospheric Pressure (weight of air) Atmospheric Pressure: weight of air per area

You can’t drink through the straw unless the atmosphere pushes the liquid. WHY no flow?

Units at Sea Level: 1 atm 760 mmHg 760 torr 101.3 kPa 1 Pascal = Same pressure as a large truck in one inch 1 Pascal = 1 Newton of force 1 m2 of area 14.7 psi

Pressure Conversions 1 atm = 760 mmHg = 760 torr = 101.3 kpa What is 475 mmHg expressed in atm? What is 103 kPa expressed in atm? 1 atm = 760 mmHg 475 mmHg x 0.625 atm 103 kPa x 1 atm = 101.3 kPa 1.02 atm

Pressure Conversions 1 atm = 760 mmHg = 760 torr = 101.3 kpa What is 720 mmHg expressed in kPa? 4. What is 2.30 atm expressed in torr? 101.3 kPa = 760 mmHg 720 mmHg x 96.0 kPa 2.30 atm x 760 torr = 1 atm 1748 torr

# of Particles Volume Temp Particles ... Volume ..… Temp .……. (collisions) Pressure Particles ... Volume ..… Temp .…….

Quick Quiz! 1) Gas pressure is affected by… A) temp, volume, and molar mass. B) temp and number of particles. C) volume and size of container. D) temp, volume, and # of particles. 9

Quick Quiz. 2) If 1 atm = 760 mmHg, then how many atm is 747 mmHg? A) 567,720 atm B) 1.02 atm C) 0.982 atm D) atm’s fo’ money yo’ 747 mmHg x 1 atm = 760 mmHg 10