key term - Concentration change

Definition

Concentration change refers to the alteration in the amount of reactants or products in a chemical system at equilibrium, impacting the system's position according to Le Chatelier's Principle. When the concentration of either reactants or products is modified, the equilibrium will shift to counteract that change, either favoring the forward or reverse reaction to restore balance. Understanding this concept is crucial for calculating new equilibrium concentrations when disturbances occur.

5 Must Know Facts For Your Next Test

1. When the concentration of a reactant is increased, the equilibrium will shift toward the products to decrease that concentration.
2. Conversely, if the concentration of a product is increased, the equilibrium shifts toward the reactants to reduce that product's concentration.
3. Decreasing the concentration of a reactant results in a shift towards the reactants, while decreasing the concentration of a product causes a shift towards the products.
4. Changes in concentration can also influence reaction rates, as more molecules increase collisions and potential reactions.
5. The magnitude of concentration changes influences how much the equilibrium will shift; larger changes tend to result in more significant shifts.

Review Questions

• How does an increase in reactant concentration affect the position of equilibrium in a chemical reaction?
  • An increase in reactant concentration causes the equilibrium to shift toward the products. According to Le Chatelier's Principle, the system will respond to this disturbance by favoring the forward reaction in order to reduce the excess concentration of reactants. This shift continues until a new equilibrium is established, where the concentrations of reactants and products are balanced again.
• Discuss how changes in concentration are utilized when calculating new equilibrium concentrations after a disturbance in a reaction system.
  • When calculating new equilibrium concentrations after a disturbance due to concentration change, it's essential to identify how much of each substance has been added or removed. This information allows for adjustments using an ICE table (Initial, Change, Equilibrium) to represent initial concentrations, changes during the shift, and final equilibrium concentrations. By applying stoichiometric relationships based on balanced chemical equations and knowing which direction the equilibrium will shift, one can effectively determine new concentrations at equilibrium.
• Evaluate how understanding concentration changes can impact real-world applications such as industrial chemical processes or biological systems.
  • Understanding concentration changes is vital for optimizing industrial chemical processes, as it helps control reaction yields and product formation by manipulating concentrations strategically. In biological systems, this knowledge informs how enzyme activity and metabolic pathways can be regulated through substrate or product concentration changes. By predicting shifts in equilibrium and their consequences, scientists can enhance production efficiency or better understand physiological responses within living organisms.

Related terms

Le Chatelier's Principle:

A principle stating that if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium shifts to counteract that change.

Equilibrium Constant (K): A value that expresses the relationship between the concentrations of products and reactants at equilibrium for a reversible reaction at a given temperature.

Reaction Quotient (Q): A ratio that compares the current concentrations of products and reactants to the equilibrium constant, used to determine the direction in which a reaction will proceed to reach equilibrium.