CHEMICAL EQUILIBRIUM
Open System
Continuously interacts with its environment
Closed System
Isolated from its surroundings
No reactants or products can leave or enter the system
Reversible Reaction
A reaction in which products can be converted back to reactants
Represented by ⇄ (in equilibrium: ⇌)
Dynamic Equilibrium
Chemical equilibrium is a dynamic equilibrium when the rate of the
forward reaction equals the rate of the reverse reaction
Le Chatelier’s Principle
When the equilibrium in a closed system is disturbed, the system
will re-instate a new equilibrium by favouring the reaction that will
oppose the disturbance
Favouring a Reaction
If the forward reaction is favoured:
1. Rate of the forward reaction > Rate of the reverse reaction
2. Equilibrium position will shift right
If the reverse reactions is favoured
1. Rate of the forward reaction < Rate of the reverse reaction
2. Equilibrium position will shift left
The reaction that counteracts the disturbance in equilibrium will be
favoured
Factors affecting Equilibrium Position
Concentration
Equilibrium will shift to decrease any increase in concentration of
either reactants or products:
1. Adding Reactantforward reaction favoured
2. Adding Productreverse reaction favoured
Equilibrium will shift to increase any decrease in concentration of
either reactants or products:
1. Removing Reactantreverse reaction favoured
Open System
Continuously interacts with its environment
Closed System
Isolated from its surroundings
No reactants or products can leave or enter the system
Reversible Reaction
A reaction in which products can be converted back to reactants
Represented by ⇄ (in equilibrium: ⇌)
Dynamic Equilibrium
Chemical equilibrium is a dynamic equilibrium when the rate of the
forward reaction equals the rate of the reverse reaction
Le Chatelier’s Principle
When the equilibrium in a closed system is disturbed, the system
will re-instate a new equilibrium by favouring the reaction that will
oppose the disturbance
Favouring a Reaction
If the forward reaction is favoured:
1. Rate of the forward reaction > Rate of the reverse reaction
2. Equilibrium position will shift right
If the reverse reactions is favoured
1. Rate of the forward reaction < Rate of the reverse reaction
2. Equilibrium position will shift left
The reaction that counteracts the disturbance in equilibrium will be
favoured
Factors affecting Equilibrium Position
Concentration
Equilibrium will shift to decrease any increase in concentration of
either reactants or products:
1. Adding Reactantforward reaction favoured
2. Adding Productreverse reaction favoured
Equilibrium will shift to increase any decrease in concentration of
either reactants or products:
1. Removing Reactantreverse reaction favoured
