Equilibrium reactions and the factors affecting them | 16-18 years

Pouring light yellow iron chloride solution into a beaker of clear potassium thiocyanate solution causing a chemical reaction changing the colour of the liquid to dark red

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Check common misconceptions about equilibrium reactions and the effects of concentration, catalysts and temperature using this lesson plan for 16–18 year olds.

In this activity, students decide whether statements about equilibrium reactions are true or false and review their decisions in a group discussion.

The resource is designed to check and make explicit the following misconceptions that:

All of a reactant added to an equilibrium mixture is used up before equilibrium is restored.
When additional reactant is added to a system in equilibrium the value of the equilibrium constant increases.
Equilibrium is reached when the concentration of reactants equals the concentration of products.
A high value of the equilibrium constant is associated with a fast reaction.
The rate of the forward reaction increases from mixing reactants until equilibrium is established.
Catalysts affect forward and reverse reactions in an equilibrium system in different ways.
Heating an equilibrium mixture decreases the rate of an exothermic reaction.

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