gen-define-chemical-equilibrium-and-give-one-short-worked-exampl-8d57

Define chemical equilibrium and give one short worked example.

# Chemical Equilibrium **Definition:** Chemical equilibrium is the state of a reversible reaction where the rate of the forward reaction equals the rate of the reverse reaction, resulting in no net change in the concentrations of reactants and products over time. ## Key characteristics: - Concentrations remain constant (not equal, but constant) - Both forward and reverse reactions continue occurring - Described by the equilibrium constant (K) --- ## Worked Example **Problem:** For the reaction N₂(g) + 3H₂(g) ⇌ 2NH₃(g), at equilibrium we have: - [N₂] = 0.50 M - [H₂] = 0.30 M - [NH₃] = 0.40 M Calculate the equilibrium constant, Kc. **Solution:** The equilibrium expression is: $$K_c = \frac{[\text{NH}_3]^2}{[\text{N}_2][\text{H}_2]^3}$$ Substituting values: $$K_c = \frac{(0.40)^2}{(0.50)(0.30)^3} = \frac{0.16}{(0.50)(0.027)} = \frac{0.16}{0.0135} = 11.9$$ **Answer:** Kc = 11.9 (no units since this can vary, though technically it's M⁻²)