Reversible reactions & equilibria

What is a reversible reaction?

When the products can react to form the reactants

How are reversible reactions represented?

⇌

What is the forward reaction?

Reactants → products

What is the backward reaction?

Products → reactants

What is dynamic equilibrium?

When the forward reaction & backward reaction occur at the same rate

Therefore, the concentration of reactants & products remains constant

Dynamic equilibrium can only be reached in a…

Closed system

What is a closed system?

When no particles can enter or escape the reaction

What is Le Chatelier’s Principle?

When the conditions change in a reaction at equilibrium, the position of equilibrium will move to counteract the change

How does temperature affect the position of equilibrium?

Increasing temperature → favours endothermic reaction

Decreasing temperature → favours exothermic reaction

How does concentration of reactant affect the position of equilibrium?

Increasing conc of reactant → favours forward reaction

Decreasing conc of reactant → favours backward reaction

How does concentration of product affect the position of equilibrium?

Increasing conc of product → favours backward reaction

Decreasing conc of product → favours forward reaction

How does pressure affect the position of equilibrium?

Increasing pressure → favours reaction that produces less moles of gas

Decreasing pressure → favours reaction that produces more moles of gas

Do catalysts affect the position of equilibrium? Why?

No

This is because catalysts speed up the rate the forward & backward reaction equally