Equilibria Flashcards
What does it mean if a chemic reaction is dynamic?
Forwards and reverse reactions proceed at the same time
What occurs in a reversible reaction at equilibrium?
Forward and reverse reactions occur at the same rate
Concentrations of reactants and products remain constant
Equilibrium can only be reach in …?
a closed system
No reactants or products can enter or leave
State Le Chatelier’s principle
A system at equilibria will shift or move to oppose any change imposed upon it
What happens to the position of equilibria if you increase the temperature?
Equilibrium will shift in the endothermic direction to oppose the change
If the forwards direction is endothermic then the reverse will be exothermic.
What would happen if you increased the concentration of one of the reactants at equilibria?
The position of equilibria will shift to the right and create more product in order to oppose the change.
Changing pressure only affects equilibria involving?
Gases
What occurs when you increase the pressure on one side of a reaction at equilibria?
Position of Eq will shift to the side with fewer gas molecules.
This reduces the pressure
Why does a catalyst not affect the position of Eq?
Increases the forward and reverse reactions at equal rates.
Doesn’t change yield but does mean equilibria will be reached faster
How are equilibrium reactions used in industry to maximise efficiency and cost?
Compromised conditions are used to achieve a high yield, at a fast rate while keeping costs low as possible.
eg. The Haber Process - NH3 production
What is Kc?
The equilibrium constant
What factors affect Kc?
Only temperature
If the T change leads to more product being produced then Kc will rise.
If the T change leads to less product being produced then Kc will fall
