Rates + Equilibrium Flashcards
rate equation
r = K[A][B] etc.
zero order
concentration have no effect on the rate
first order
rate increases by same factor as concentration increases
second order
rate increases by conc increase factor²
rate units
mol/dm3/s
half life
Time taken for half the reagent to be used up
half life in first order reaction
always the same
use of half lives
to determine whether or not a reaction is first order
Arrhenius equation shows
effect of changing temp/activation energy on the rate constant
Kc equation
Kc = [products] / [reactants]
mole fraction equation
= moles of gas A \ total moles of gas
partial pressure
the pressure one gas would except if it was the only gas in the container
partial pressure equation
pp = mol frac. x total pressure
only factor that changes Kc
temperature
dynamic equilibrium
both the foward and backwards reactions are taking place, at the same rate
dynamic equilibrium
both the forwards and backwards reactions are taking place, at the same rate
effect of pressure on position of equilibrium
pressure increase = favours the side with fewer gas molecules (reducing pressure of the system)
effect of temperature on position of equilibrium
temp increase = favours endothermic reaction
effect of concentration on position of equilibrium
conc. increase = favours side with fewer moles
Kc > 1 =
equilibrium position is towards PRODUCTS
Kc < 1 =
equilibrium position is towards REACTANTS
Kc = 1 =
equilibrium is HALFWAY between products and reactants