Key Characteristics of Equilibrium
* Rates are equal: The forward reaction rate (reactants turning into products) is equal to the reverse reaction rate (products turning back into reactants). This means that the concentrations of reactants and products remain constant over time.
* Net change is zero: While individual reactions are still occurring, the overall change in the system is zero. There's no observable change in the amounts of reactants or products.
* Dynamic process: Equilibrium is not a static state. Reactions continue to happen, but at an equal pace in both directions. It's like a tug-of-war where both sides are pulling with equal force, resulting in no movement.
What Doesn't Happen at Equilibrium
* Reactions stop: Reactions continue to occur, just at equal rates.
* Concentrations are equal: Reactant and product concentrations may be different, but they remain constant.
* The system is "locked": Equilibrium is a dynamic state. Applying stress (like changing temperature or pressure) will shift the equilibrium position to relieve the stress.
Example
Imagine a reversible reaction:
* A + B ⇌ C + D
At equilibrium:
* The rate of A + B → C + D is equal to the rate of C + D → A + B.
* The concentrations of A, B, C, and D remain constant.
* The reaction is still happening, but the net change in concentrations is zero.
Important Points
* Equilibrium is affected by conditions: Changes in temperature, pressure, or concentration can shift the equilibrium position to favor either the forward or reverse reaction.
* Equilibrium constant (K): This value describes the relative amounts of reactants and products at equilibrium. A higher K means the products are favored at equilibrium.
Let me know if you have any other questions about chemical equilibrium!
