Equilibrium [H]

This lesson covers dynamic equilibrium, a Higher tier topic in the AQA GCSE Chemistry specification. When a reversible reaction takes place in a closed system, it eventually reaches a state of equilibrium. Understanding what equilibrium means, how it is established, and what it looks like on a graph is essential for achieving top grades at GCSE.

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What Is Dynamic Equilibrium?

When a reversible reaction occurs in a closed system, it reaches a point where the rate of the forward reaction equals the rate of the reverse reaction. This is called dynamic equilibrium.

At equilibrium:

• The forward and reverse reactions are both still occurring — the reaction has not stopped
• The rates of the forward and reverse reactions are equal
• The concentrations of reactants and products remain constant (but not necessarily equal)