Equilibrium Constant

The position of a system in dynamic equilibrium can be described mathematically, using the equilibrium constant, K_C.

We need to know how to:

1. Write a K_C expression for an equilibrium
2. Calculate K_C (when given the concentrations of reactants and products at equilibrium).
3. Calculate the concentration of a reactant/product (when given the K_C value and concentrations of all other reactants and products).
4. Explain whether the equilibrium "favours" the forward or reverse reaction, based upon the K_C value.

We can then use this knowledge to apply le Chatelier's Principle to changes in the equilibrium position due to outside influences (our next key concept).