Worksheets and lesson ideas to challenge students aged 11 to 16 to think hard about equilibria and reversible reactions (GCSE and Key Stage 3)
Many students struggle with the concept of dynamic equilibrium, incorrectly assuming that equilibrium refers to a “balance” between reactants and products. The resources below strive to encourage students to understand the concepts in the context of a simple physical change involving H2O(l) moving to H2O(g). Students move on to apply their knowledge to chemical equilibria.
Modelling dynamic equilibria
GCSE models to help understand equilibria. This simple model uses a snowball fight to show students how concentrations of reactants and products remain constant at equilibrium. This lesson can be further developed to help students understand the concept of position of equilibrium.
GCSE activity to understand dynamic equilibria. The worksheet describes a simple model of evaporation and condensation in a closed system. Students use the model to understand what happens at dynamic equilibrium to rates of forward and reverse reactions and to the concentration of reactants and products. (PDF)
Changing the position of equilibrium
GCSE worksheet on the chemistry of cola and Le Chatelier’s principle. Students consider how to make the perfect drink of cola. They use their knowledge of equilibria and how changes can affect the position of equilibrium according to Le Chatelier’s principle. (PDF)
GCSE starter activity on position of equilibrium. Students are given two statements about a reaction at equilibrium. They use this information to determine whether the forward reaction is exothermic/endothermic and deduce stoichometry of gaseous reactants and products. This is an excellent activity to get students thinking about Le Chatelier’s principle. (PDF)
The Haber process is perhaps the most important synthetic chemical reaction on Earth. The story of its founder, Fritz Haber, is an incredible one – a Jewish chemist who discovered the chemicals that were later used to kill members of his own family. A story that illustrates the good and evil science can do and is described brilliantly here by the BBC’s Radio Four in The Chemist of Life and Death.
Compromise conditions and the Haber Porcess
GCSE worksheet on the Haber process and compromise conditions. This activity gets students to think deeply about compromise conditions. They need to think about the balance between rate, yield and cost. (PDF)