chem H unit 6

gases

pressure formula

pressure = force/ area

how do gases move

constant random motion

what happens when 2 gas molecules collide

they have elastic collisions (nrg is not lost)

how do IMF’s affect gases

the gas particles are too far apart to attract each other

does the volume of each molecule matter

No, they are so far apart it doesn’t matter

Kinetic energy def

the energy of motion

kinetic energy equation

KE = ½ mass x velocity²

two different gases have the same KE if

they are at the same temperature

difference between real and ideal gases

real gases have volume and attract each other

when does gas behave real

low temperatures, high pressure

how do gases exert pressure

equally, in all directions, on all surfaces

how many mmHg is equal to 1 atm

760 mmHg

manometer if the mercury is higher on the gas side

pgas = patm - h

Barometer if the mercury is higher on the atm side

pgas = patm + h

how is p related # of molecules

p is directly related to # of molecules because more molecules = more collisions

how does the mass of a molecule affect pressure

it doesn’t

how does mass affect speed

heavy molecules move slower, light ones move fast

how is p related to volume

p is inversely related to volume bc less volume = more collisions

how is p related to temp

p is directly related to temp bc higher temp = more KE = more collisions

combined gas law eq

(pressure1 x volume1) / temp = (pressure2 x volume 2)/ temp

partial pressure law

P total = Pa + Pb + Pc …