Gases - Chemistry Study Notes

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Gases pressure is exerted by gas particles hitting the walls of the containerweakest intermolecular force (hydrogen) --> out of all the gases going to most obey “Gas particles neither attract nor repel each other” (#3 of kinetic theory of gases)PressureWhy is stepping on a nail more painful than lying on a bed of nails?-force exerted by your mass is spread out over a larger area (when one lies on a bed of nails) compared to when you step on a nail, so you feel less pain.

equation for pressure --> P = F/A F - force, A - Areachanging the area --> increase the area (pressure decreases)decrease in area – pressure increasesliquids and gases can also exert pressureBarometer --> measures air pressureair particles hit the surface of surface of mercury-the higher the room pressure --> more air molecules hitting the surface, exerting downward pressure causing the level of mercury in the tube to risethe average room pressure is 760 mm of the mercuryIdeal Gas – behaves according to the Kinetic Theory of Gases-no gas does this completely-Gases do exhibit minimum amounts of attraction (H2 , He show the least)-All particles have volume (its only relevant at extremely high pressures)Boyle’s LawP (pressure) and V (volume); variable → T (temperature) & n (constant - # of moles)-relationship between P and V is inversely proportional-downward curve starting at high volume (neither approaches zero)1) If volume is doubled – pressure decreases by half2) If pressure is tripled – volume decreases to 1/3 of the original volumePV = constantP1V1 = P2V2Units of pressure: Pascals (Pa)PSI1 mm Hg = 1 torratmair pressure at sea level - 1 atm1 atm = 760 mm Hg = 760 torrimploding soda can --> external pressure > internal pressurewhen you heat the soda can with water inside → little bit...