Chemical Equilibria Flashcards
When is a chemical reaction in the state of equilibrium?
When the rate if the forward reaction is equal to the rate of the reverse reaction
What will the equilibrium do if we change concentration, pressure or temperature
Counteract the change
A+B - C+D
What happens if A or B is increased?
More C or D is produced until equilibrium established- so equilibrium shifts right
A+B - C+D
What is C or D is removed
Equilibrium shifts right with more C or D produced
If forward reaction is exothermic…..
Reverse must be endothermic
What would a fall in temperature cause?
The reaction will favour exothermic (gives out heat)
What would increase in temperature cause?
The reaction would favour endothermic side which absorbs heat
What would increasing pressure do to equilibrium?
Equilibrium will shift to the side with fewer moles
What would decreasing pressure do to the equilibrium
Equilibrium shifts in direction with most moles
When are effects of pressure applied to reactants is products
When they are in the gaseous state
What if both sides had equal moles? (Pressure)
No effect
Describe a catalyst’s effect in equilibrium
Catalysts have no effect on equilibrium, they do allow reactions to reach equilibrium quicker
What are catalyst’s role in potential energy diagrams?
Form temporary bonds with reactants to lower activation energy.
Why is equilibrium not affected in potential energy diagrams?
Since they lower activation energy of forward reaction and reverse reaction by the same amount
