Equilibrium shifts refer to changes in the relative amounts of products and reactants when a system reaches chemical equilibrium. These shifts occur in response to changes in concentration, pressure, or temperature applied to an already established equilibrium.
If there are changes in concentration for any species involved in an equilibrium reaction, it can cause an equilibrium shift by affecting the relative amounts of products and reactants.
Pressure Changes: For reactions involving gases, changes in pressure can cause equilibrium shifts since the number of moles of gas on each side affects the balance.
Temperature Changes: Altering the temperature can lead to equilibrium shifts since it affects the value of the equilibrium constant (K) and changes reaction rates.