Question

Continuous removal of one of the products of a chemical reaction has the effect of causing the reaction to go to completion. Explain this fact in terms of Le Châtelier's principle.

Short answer

When a product of a chemical reaction is continuously removed, it disturbs the equilibrium of the system. To counteract this change, in accordance with Le Châtelier's principle, the system shifts towards the side of the products, driving the reaction towards completion.

Step-by-step solution

Explaining Le Châtelier's Principle

Le Châtelier's Principle can be simplified as a law of 'cause and effect' in chemistry. If there's a change in the conditions of a chemical system at equilibrium, the system will react in such a way as to counteract that change.

Relation to Removal of a Product

When one of the products in a chemical reaction is continuously removed from the mixture, it disturbs the equilibrium condition. According to Le Châtelier’s principle, the equilibrium will shift in the direction where it can counteract this change.

Explaining the Effect on Completion of the Reaction

If a product is constantly removed, the system will respond by trying to produce more of that product to restore the equilibrium. Thus, the reaction is pushed towards the 'product' side until all reactants have been used up and the reaction goes to completion.

Key concepts

chemical equilibrium

When a chemical reaction reaches a state of balance, it is said to be in chemical equilibrium. At this point, the rate at which reactants are converted to products is equal to the rate at which products revert to reactants. This doesn't mean that the amounts of reactants and products are equal, but rather that their concentrations remain constant over time.
In this state, the forward and reverse reactions continue to occur, but there's no overall change in the concentrations of reactants and products. Chemical equilibrium can be achieved in a closed system where no substances can enter or leave.
If the conditions affecting the reaction are altered, such as changes in concentration, pressure, or temperature, the equilibrium can shift. This is where Le Châtelier's principle comes into play, helping us predict the direction of the shift to restore balance.

product removal effect

The effect of removing a product from a chemical reaction highlights the dynamic nature of chemical equilibria. According to Le Châtelier's principle, if a product in a balanced chemical reaction is removed, this disruption will cause the system to shift towards the product side to counteract the change.
This shift occurs because the system naturally adjusts to restore equilibrium by producing more of the missing product. This constant adjustment demonstrates the system's attempt to maintain equilibrium under new conditions, illustrating the 'cause and effect' nature of chemical reactions.

• Re-equilibration results in more reactants being used up to form additional product.
• The ongoing removal of a product effectively 'drives' the reaction forward.

Understanding this behavior is crucial in chemical processes and industrial applications where maximizing product yield is desired.

reaction completion

Reaction completion signifies the process where all reactants are fully converted into products. This situation can be manipulated by removing one of the products from a chemical reaction at equilibrium.
By continuously removing a product, the reaction is driven forward until no reactants are left, and thus, it reaches completion. It's as if the system "wants" to compensate for the loss by speeding up the production of the removed product at the expense of the reactants.
This concept is significant in many practical scenarios, such as synthesis reactions in the chemical industry, where achieving complete conversion of reactants can be economically beneficial. By understanding the influence of removing a product, chemists can effectively control reaction pathways to optimize yields.