Reversible Reactions and Equilibria

Students mainly experience chemical reactions that appear to go to completion. When they meet a reaction that does not go to completion but which has a reverse reaction occurring they find the concept difficult to understand.

One major misconception students have about equilibria is that they think equilibria positions are fixed and once achieved there is no movement of particles between the two 'sides' i.e. they believe that equilibria are static not dynamic.

Le Chatelier's Principle is a way of predicting changes to an equilibrium position under some circumstances but is generally wrongly applied due to the misunderstanding about the equilibrium position.

Rate and equilibria are often confused because students think that the rate of one reaction may change while the other slows or remains constant. They have not grasped that rate applies to the system as a whole.

It is important to use a wide range of reversible reactions to help get these ideas across to the students.

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