Le Chatelier Flashcards
What is the common ion effect?
The common ion effect occurs when the addition of an ion already present in a solution reduces the solubility of a salt or shifts an equilibrium away from the formation of more of that ion.
How does the common ion effect influence equilibrium?
The addition of a common ion shifts the equilibrium position according to Le Chatelier’s principle, typically reducing the concentration of ions formed by dissociation.
Give an example of the common ion effect.
Adding NaCl to a solution of AgCl decreases AgCl’s solubility because Cl⁻ is a common ion. The equilibrium shifts toward the solid AgCl.
How does a change in pressure affect equilibrium in gaseous systems?
Increasing pressure shifts equilibrium toward the side with fewer gas molecules. Decreasing pressure shifts it toward the side with more gas molecules.
What happens to equilibrium when pressure is increased in the reaction: N₂(g) + 3H₂(g) ⇌ 2NH₃(g)?
The equilibrium shifts to the right (toward NH₃) because there are fewer gas molecules on the product side (2 vs. 4 on the reactant side).
Does pressure affect equilibrium in systems with no gas molecules?
No, pressure changes only affect equilibria involving gaseous components.
What role does volume play in pressure-related equilibrium shifts?
Decreasing the volume increases pressure, favoring the side with fewer gas molecules. Increasing volume decreases pressure, favoring the side with more gas molecules.
How does adding an inert gas at constant volume affect equilibrium?
Adding an inert gas at constant volume does not shift equilibrium, as it does not change the partial pressures of the reactants or products.
