Chemistry - Gas Laws

Kinetic-Molecular Theory

1. Gases consist of large amounts of tiny particles far apart in constant, random motion

2. Collisions are elastic, BOUNCE with no loss of energy

3. NO forces of attraction/repulsion between particles

Pressure

Force per unit area

(amt of force the gas is exerting onto container

P = F/A

measured in kPa, atm, mmHg

Conversions

101.3 kPa = 1 atm = 760 mm Hg

Volume

Measure of space occupied

Measured in L or cubic meters

Temperature

Average kinetic energy

in KELVIN

C-K add 273

Moles

Number of gas particles

PV/T = PV/T

using when COMPARING two items of same unit

TEMP ALWAYS IN K

PV=nRT

“pervert”

P IN ATM

V IN L OR cubic DECImeters

n is MOLES

R = 0.0821

T=K

STP

Standard Temp+Pressure

0^oC/273^oK and 1 atm

Conversions for Stoichiometry

1 mole

6.022×10²³ atoms/molecules

grams of element

coefficients

22.4 Liters (STP!)

Effusion

Movement of particles through a small opening

Diffusion

Movement of particles from HIGH to LOW concentration

Speed of movement is dependent on 2 things

Temperature

Mass

Temperature Higher makes particles move

Faster, curve will be stretched out

Particle is heavier particle moves

slower, makes a higher curve

Graham’s Law

relates speed and molecular weight by comparing two gases

mv²=mv²

Dalton’s Law

sum of pressures is equal to total pressure

add the pressures..