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

(weight of air) measured with a barometer empty space (a vacuum) weight of Hg h 760 mm Atmospheric Pressure (weight of air) measured with a barometer Atmospheric Pressure: weight of air per area (14.7 psi) psi -> pounds per square inch

You can’t drink through the straw (in a closed container) unless the atmosphere pushes the liquid. WHY no flow?

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

# 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. 6

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 747 mmHg x 1 atm = 760 mmHg 7