What is dynamic equilibrium?
A chemical reaction should not be thought of as compounds completely changing into a new compound and staying that way, often in whats known as reversible reaction, the products and reactants of a chemical reaction will constantly transform one substance to another. Dynamic equilibrium exists only during reversible chemical reactions in a closed system. In such a reaction, when the reactants are transformed into products and the products are transformed back into reactants at an equal rate, the reaction is said to be at dynamic equilibrium. This does not mean that there is always the same amount of products compared to reactants, it means that the rate at which they are changing from products to reactants is the same. During dynamic equilibrium the net concentrations of all substances involved stays constant.
Where is dynamic equilibrium used?
Dynamic equilibrium is used in many industrial processes, such as the synthesis of ammonia (known as the Haber Process), the production of sodium carbonate (the Solvay Process) as well as the formation of methanol. It is also used on a smaller scale in everyday chemical reactions such as the aqueous solution of salt dissolved in water, the dissociation of acetic acid, as well as bottled soda.
How is dynamic equilibrium manipulated for our benefit?
Le Chatelier's principle states that any change made to reaction at equilibrium will cause a shift in the direction that will minimize change. This means that a reaction at equilibrium wants to stay at equilibrium; therefore, when a change is made to the reaction (change in temperature or volume) the reaction will shift, producing more products or reactants, in order to keep the reaction at equilibrium. Using this knowledge of Le Chatelier's principle, we can make changes to the reaction (change the temperature or pressure for example) in order to make the reaction produce more products and increase product yield. This is a very useful technique commonly practiced in industries which use the Haber Process, Solvay Process and much more.