The Common Ion Effect is a phenomenon that describes how the equilibrium constant of a chemical reaction changes when the concentration of common ions is varied...
The Common Ion Effect is a phenomenon that describes how the equilibrium constant of a chemical reaction changes when the concentration of common ions is varied. Common ions are ions that appear in multiple chemical species, such as hydrogen ion (H+), sodium ion (Na+), chloride ion (Cl-), and hydroxide ion (OH-) in aqueous solutions.
How does the Common Ion Effect work?
The Common Ion Effect arises due to the influence of common ions on the equilibrium constant of a chemical reaction. When the concentration of common ions increases, it shifts the equilibrium towards the side of the reaction where the concentration of these ions is lower. This is because the common ions compete with the reactants for binding to the surface of the solid or liquid phase of the reactants.
Examples:
H2(g) + O2(g) -> H2O(l)
If the concentration of hydrogen ions (H+) is increased, it will shift the equilibrium towards the left, resulting in fewer hydrogen molecules and more water molecules being formed.
The Common Ion Effect is a fundamental concept in chemical equilibrium and helps chemists understand how changes in concentration affect the position of equilibrium