5.3 Flashcards
Question: What is a reversible reaction?
Answer: A reversible reaction is one where the reactants can form products, and the products can react to reform the original reactants.
Question: How are reversible reactions represented in chemical equations?
Answer: Reversible reactions are represented using two opposing arrows, each with half an arrowhead, indicating the forward and reverse reactions occurring simultaneously
Question: How can the direction of a reversible reaction be changed?
Answer: The direction of a reversible reaction can be changed by altering the reaction conditions, such as temperature or pressure.
Question: What are the energy changes associated with reversible reactions?
Answer: If the forward reaction of a reversible reaction is exothermic, then the backward reaction is endothermic, and vice versa.
Question: What is dynamic equilibrium?
Answer: Dynamic equilibrium occurs when the rate of the forward reaction equals the rate of the backward reaction, resulting in a constant concentration of reactants and products over time.
Question: In what type of system can dynamic equilibrium occur?
Answer: Dynamic equilibrium can only occur in a closed system, where none of the participating chemical species are able to leave the reaction vessel and nothing else can enter.
Question: Provide an example of a dynamic equilibrium.
Answer: An example of a dynamic equilibrium is the Haber process, where hydrogen and nitrogen react to form ammonia, and the forward and backward reactions reach equilibrium in a closed system.
Question: How can one determine when equilibrium is reached from a graph?
Answer: To determine when equilibrium is reached from a graph, look for the point where the graph levels off into a horizontal line, indicating that the rates of the forward and backward reactions have become equal
Question: What is Le Chatelier’s Principle?
Answer: Le Chatelier’s Principle states that when a change is made to the conditions of a system at equilibrium, the system will shift to oppose that change.
Question: How does Le Chatelier’s Principle apply to changes in concentration?
Answer: An increase in the concentration of a reactant or product will cause the equilibrium to shift towards the side with fewer moles of substances, while a decrease will cause the equilibrium to shift towards the side with more moles of substances.
Question: How does Le Chatelier’s Principle apply to changes in temperature?
Answer: When temperature increases, the equilibrium will shift in the endothermic direction to absorb the excess heat, while decreasing temperature will cause the equilibrium to shift in the exothermic direction to counteract the loss of heat.
Question: How does Le Chatelier’s Principle apply to changes in pressure?
Answer: Increasing pressure will shift the equilibrium towards the side with fewer moles of gas molecules, while decreasing pressure will shift the equilibrium towards the side with more moles of gas molecules
Question: What is the effect of increasing pressure on a reaction with an equal number of moles of gas on both sides?
Answer: Increasing pressure will have no effect on the equilibrium position if there are the same number of moles of gas on both sides of the reaction.
Question: Can you explain Le Chatelier’s Principle using a simple analogy?
Answer: Le Chatelier’s Principle can be thought of like a grumpy toddler trying to do the opposite of what is done to them. The system responds to changes by attempting to restore equilibrium, much like the toddler’s behavior.
Question: How does Le Chatelier’s Principle influence chemical economics?
Answer: Le Chatelier’s Principle is key to controlling the costs of chemical products by maximizing yields through manipulation of reaction conditions to favor the production of desired products.
