Intermolecular forces/Liquid/Gas phase/Kinetics

Hydrogen bonding (strongest)

F-H, O-H, or N-H bond required in a pure substance

F, O, or N to hydrogen bond with H2O

dipole-dipole forces (2nd strongest)

intermolecular force for polar molecules

London dispersion forces (Van der Waals)

A temporary or transient dipole

All molecules have these and the greater the weight and surface area, the greater the London dispersion forces

Higher intermolecular forces lead to —-

Higher boiling point

higher heat of vaporization

higher viscosity

higher surface tension

lower vapor pressure

Ideal Gas Law

PV=nRT

Boyle’s Law

P = 1/V

Charle’s Law

V = T

Avogadro’s Law

V = n

combined gas law

PV/nT = PV/nT

catalyst

Speeds up a reaction by lowering the activation energy, by providing an alternate mechanism for the rxn to occur

• NOT consumed in a rxn

• does NOT shift equilibrium

kinetic product

lower activation energy

favored at low temperatures

thermodynamic product

Overall lower energy product

favored at higher temperatures

reaction order zero

(A) = (A)₀ - kt

t1/2 = (A)₀/2k — the less reactant the shorter it will take

1st order rxn

ln(A) = ln(A)₀ -kt

t1/2= 0.693/k — does not matter how much you have

2nd order rxn

1/(A) = 1/(A)₀ + kt

t1/2 = 1/k(A)₀ — the less of a reactant the longer it will take

K >> 1

products favored at equilbrium

K << 1

reactants favored at equilibrium

Q < K

shift right

Q > K

shift left

Q = K

at equilibrium