Chemical Equilibrium
Equilibrium is reached in a closed system when the forward and reverse reactions occur at the same rate, so concentrations stay constant.
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Equilibrium is reached in a closed system when the forward and reverse reactions occur at the same rate, so concentrations stay constant.
- Le Chatelier's principle predicts shifts
- The reaction does not stop
- Needs a closed system
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Chemical Equilibrium?
Within Chemistry, which covers atoms, bonding, reactions, the periodic table, organic chemistry and the chemistry of everyday life, this topic explains Chemical Equilibrium. Chemistry links what you can see in the lab to the particles and bonds behind it, so each topic here shows that link in a model.
Check that you can explain Chemical Equilibrium in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Chemical Equilibrium helps you explain why substances behave as they do, from cleaning products and food to medicines.
Chemical Equilibrium in detail
In a closed system, a reversible reaction reaches dynamic equilibrium when the rate of the forward reaction equals the rate of the reverse reaction. The concentrations of reactants and products stay constant, though both reactions are still taking place.
Le Chatelier's principle says that if conditions change, the equilibrium shifts to oppose the change. Raising the temperature favours the endothermic direction, increasing pressure favours the side with fewer gas molecules, and adding more reactant shifts the equilibrium toward products. This principle guides the choice of conditions in industry.
How the interactive helps you understand Chemical Equilibrium
Watch the reaction model in the interactive. Use any sliders or buttons it offers to change the values and see how the reaction model responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Chemical Equilibrium.
Real-life uses and examples
- Link Chemical Equilibrium to everyday products such as cleaning agents, food and medicines.
- Read a chemical equation or diagram and work out what Chemical Equilibrium shows.
- Explain Chemical Equilibrium in an exam by linking the particles involved to what you observe.
Common mistakes to avoid
- Mixing up the names of substances or ions when you describe Chemical Equilibrium.
- Describing what happens without explaining the particles or bonds involved.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Chemical Equilibrium
What is Chemical Equilibrium?
Equilibrium is reached in a closed system when the forward and reverse reactions occur at the same rate, so concentrations stay constant.
What are the most important points about Chemical Equilibrium?
The main points are: Le Chatelier's principle predicts shifts; The reaction does not stop; Needs a closed system.
Why is Chemical Equilibrium useful?
Understanding Chemical Equilibrium helps you explain why substances behave as they do, from cleaning products and food to medicines.
How can I practise Chemical Equilibrium?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Chemical Equilibrium?
Related topics in Chemistry include Fuels and Combustion, Alkenes, Alcohols.