Equilibria flashcards
How does a closed system differ from an open system?
A closed system does not exchange matter with its surroundings, while an open system does.
What is dynamic equilibrium?
A state where the forward and reverse reaction rates are equal, and concentrations remain constant.
How does increasing temperature affect an exothermic reaction at equilibrium?
It shifts equilibrium to favour the reactants (left).
How does increasing pressure affect a gaseous equilibrium?
The system shifts to the side with fewer gas molecules.
What is the equilibrium constant (K)?
A ratio that expresses the relative concentrations of products to reactants at equilibrium.
What happens if a catalyst is added to an equilibrium system?
It speeds up both forward and reverse reactions but does not change equilibrium position.
How does activation energy influence reversibility?
Lower activation energy makes reversibility more likely; high activation energy favours irreversibility.
What must happen for dynamic equilibrium to be reached?
The forward and reverse reaction rates must be equal, and concentrations must remain constant.
How does the rate of the forward reaction change over time?
It decreases as reactants are consumed.
How does the rate of the reverse reaction change over time?
A: It increases as products are formed.
It increases as products are formed.
How does temperature affect K?
For exothermic reactions, K decreases with temperature increase; for endothermic reactions, K increases.
What is the reaction quotient (Q)?
A ratio of product/reactant concentrations at any point, not necessarily equilibrium.
What does it mean if:
-Q = K
-Q > K
-Q < K
Q = K system is at equilibrium
Q > K reaction shifts left (reverse reaction favoured)
Q < K reaction shifts right (forward reaction favoured)
If K is large, what does that indicate?
The reaction heavily favours products.
If K is small, what does that indicate?
The reaction heavily favours reactants.
How does adding a reactant affect equilibrium?
It shifts right (forward reaction favored).
How does removing a reactant affect equilibrium?
It shifts left (reverse reaction favored).
