Gen Chem 2 - Chapter 5

Molecular Gas Theory - mostly Gas Laws tbh

Boyle’s Law

the relationship between Gas pressure and volume is CONSTANT!

P1 V1 = P2 V2

Charles’ Law

gas temperature and volume are proportional when pressure is constant

V1/T1 = V2/T2

Avogadro’s Law

gases of equal volumes have the same amount of moles at constant temperature and pressure

V1/n1 = V2/n2

Ideal gas law

PV = nRT

P = pressure
V = volume
n = moles of gas
R = gas constant (depends on units!)

T = temperature (Celsius → Kelvin!)

Finding density of a gas

d = PM/RT

d = density
P = pressure
M = molar mass
R = constant (depends on units)
T = temperature (Celsius → Kelvin!)

Dalton’s Law of Partial Pressure

Dalton’s Law: Ptotal = P1 + P2 + P3 etc . . .
Partial Pressure: Xa (mole fractions) * Ptotal

Xa (Mole fractions): na (moles of gas) / ntotal (total moles of all molecules)

root mean squared

U rms = square root of 3RT/M

R = 8.314 mol
M = Kg/mol

Temp increase = SPEED INCREASE
Molar mass increase = SPEED DECREASE

Diffusion

molecules move from high concentrated areas to low concentrated areas

Effusion

gas escapes through a narrow opening into a vacuum

Graham’s Effusion Law

Rate 1/ Rate 2 = square root of M2/M1

(where M = molar mass)

Kinetic Molecular Theory

Particles have random movement + no attractive forces

Kinetic energy is proportional to temperature + not lost when particles collide