To answer this question correctly, let's recall some fundamental principles about chemical equilibrium and how it responds to changes, or "stresses," which is described by Le Chatelier's Principle.
Le Chatelier's Principle states that if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium will shift to counteract the change. This principle can apply to changes in concentration, temperature, pressure, or volume.
Here's a detailed breakdown of what happens when stress is applied to an equilibrium reaction:
1. Change in Concentration: If the concentration of one of the reactants or products is changed, the equilibrium will shift to oppose the change. For example, adding more reactant will shift the equilibrium to produce more products, while removing a reactant will shift the equilibrium to produce more reactants.
2. Change in Temperature: The effect of temperature on equilibrium depends on whether the reaction is endothermic or exothermic. For an endothermic reaction (heat is absorbed), increasing temperature shifts the equilibrium towards the products. For an exothermic reaction (heat is released), increasing temperature shifts the equilibrium towards the reactants.
3. Change in Pressure: For gaseous reactions, changing the pressure affects the equilibrium position. Increasing pressure favors the side of the reaction with fewer gas molecules. Decreasing pressure favors the side with more gas molecules.
4. Change in Volume: Changes in volume are related to changes in pressure. Increasing the volume decreases the pressure and favors the side with more gas molecules, while decreasing the volume increases the pressure and favors the side with fewer gas molecules.
Answer to the Multiple Choice Question:
When stress is applied to an equilibrium reaction, the most likely result is that the equilibrium will shift to counteract the stress applied. This means that the system will adjust itself either by forming more reactants or products, depending on the nature of the stress applied, to restore equilibrium as per Le Chatelier's Principle.
Therefore, the correct answer for this question is:
The equilibrium will shift in a direction that reduces the effect of the stress.
