Question 1: Define dynamic equilibrium in the context of chemical reactions.

Answer: Dynamic equilibrium is a state in a reversible chemical reaction where the forward and reverse reactions occur at the same rate, resulting in no net change in the concentrations of reactants and products.

Question 2: Explain what happens to the concentrations of reactants and products when a system reaches dynamic equilibrium.

Answer: The concentrations of reactants and products remain constant over time because the rates of the forward and reverse reactions are equal.

Question 3: Describe the mechanism by which equilibrium is established in a reversible reaction.

Answer: Equilibrium is established when the rates of the forward and reverse reactions become equal, leading to a stable ratio of reactants and products that no longer changes with time.

Question 1: In a reversible reaction, the rate of the forward reaction is 0.05 mol/L·s, and the rate of the reverse reaction is 0.05 mol/L·s at equilibrium. If the initial concentration of reactant A was 2.0 mol/L, what is the concentration of reactant A at equilibrium assuming no other changes? (Use the rate law: Rate = k [A])

Answer: The concentration of reactant A at equilibrium is approximately 1.0 mol/L.

Question 2: Calculate the equilibrium constant (Kc) for a reaction where the concentration of reactant is 0.3 M and the concentration of product is 0.6 M at equilibrium.

Answer: Kc = 2.0

Question 1: Describe an experimental setup to observe the establishment of dynamic equilibrium in a reversible reaction. Include variables that need to be controlled and safety precautions.

Answer: An experiment could involve mixing a reversible reaction mixture, such as iodine and starch in an aqueous solution, and observing color changes over time. Variables to control include temperature, concentration, and pressure. Safety precautions include wearing gloves and goggles, handling chemicals carefully, and working in a well-ventilated area.

Question 1: In an experiment, the concentration of reactant B decreases from 1.0 M to 0.6 M over 10 minutes while the concentration of product C increases from 0.2 M to 0.6 M. What does this data suggest about the reaction's state, and what can you infer about the rate of the forward and reverse reactions?

Answer: The data suggests the reaction is moving toward equilibrium with the forward reaction producing more product C. The rates of the forward and reverse reactions are approaching equality as concentrations stabilize.

Question 1: Explain why the rate of the forward and reverse reactions are equal at equilibrium, but the concentrations of reactants and products remain constant. Provide a detailed explanation suitable for a 6-mark question.

Answer: At equilibrium, the forward and reverse reactions occur simultaneously at the same rate, so there is no net change in the amounts of reactants and products. Although reactions continue to occur, they do so at equal rates, resulting in constant concentrations. This dynamic balance is maintained as long as conditions remain unchanged.

Question 1: Provide an example of a real-world process that relies on dynamic equilibrium and explain its importance.

Answer: The Haber process for ammonia production relies on dynamic equilibrium, allowing continuous synthesis of ammonia at high temperatures and pressures. Maintaining equilibrium conditions ensures maximum yield, which is crucial for fertilizer manufacturing.