ES - equilibria *01 Flashcards
characteristics of a dynamic equilibrium
the forward reaction will be going at the same rate as the backward reaction.
the amounts of reactants and products won’t be changing
in a closed system
what is a reversible reaction?
the reaction goes both ways
what does the position of equilibrium tell you?
how much reactant and how much product you’ll have at equilibrium
if equilibrium lies to the left - more reactants than products
if equilibrium lies to the right - more products than reactants
what is Kc?
an equilibrium constant
how can you work out Kc?
need concentrations
general reaction
aA + bB cC + dD
Kc = [C]^c x [D]^d / [A]^a x [B]^b
what does Kc tell us?
the position of the equilibrium
the larger the Kc value, the further to the right the equilibrium lies
what does it mean if: Kc»_space; 1
equilibrium lies far to the right
what does it mean if: Kc > 1
the equilibrium lies to the right
what does it mean if: Kc «_space;1
equilibrium lies far to the left
what does it mean if: Kc < 1
equilibrium lies to the left
does changing concentration change Kc
no
does changing temperature change Kc
Yes
increasing temp. means adding heat so equilibrium will shift in the endothermic direction to absorb the heat
decreasing temp. removes heat so equilibrium shifts in the exothermic direction to try and replace heat
does changing pressure change Kc
no
equli. position changes
increasing pressure shifts equilibrium to the side with fewer gas molecules, this reduces the pressure
decreasing the pressure shift equilibrium to side with more gas molecules, this raises the pressure
opposing change
a reversible reaction will always oppose change
if increase temp. reaction will work to decrease it ect.
