The Dance of Dynamic Balance
📖 The Dance of Dynamic Balance
Equilibrium is like a stubborn balance scale! If you add weight to one side, the scale shifts to oppose the change. Add more reactants? The system shifts to make more products. Increase pressure? It shifts to the side with fewer gas molecules. The system always tries to counteract what you do — that's Le Chatelier's Principle!
Chemistry glossary
- What does 'dynamic equilibrium' mean?
- Forward and backward reactions happen at the same rate, so concentrations stay constant
A reversible reaction is one that can go in both directions — products can turn back into reactants. The symbol ⇌ (two half-arrows pointing in opposite directions) is used to show this. You will see it in equations such as N₂ + 3H₂ ⇌ 2NH₃, meaning the reaction can proceed both left-to-right and right-to-left. (If you h
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🧠 Memory Aid: Le Chatelier = The Lazy System
Think of the equilibrium system as lazy and oppositional — it always does the opposite of what you try to do to it:
- Add heat? → System absorbs heat (endothermic direction)
- Remove heat? → System releases heat (exothermic direction)
- Add reactant? → System uses it up (shifts to products)
- Increase pressure? → System reduces molecules (smaller side)
The system is like a teenager asked to do chores — it always does the opposite of what you want! Whatever change you make, it tries to undo it.
For pressure specifically: COUNT the gas molecules on each side. High pressure shifts to the side with fewer gas molecules (because that reduces pressure).
Now try it yourself
Quiz · Question 1 of 23
At dynamic equilibrium, which of the following is true?
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This topic in real past papers
Every real exam question we've found on equilibrium (ht), with a full worked answer.