Gen Chem II: Ch. 14 Equilibrium

What is chemical equilibrium?

Chemical equilibrium occurs when the rates of the forward and reverse reactions are equal and the concentrations of reactants and products remain constant.

What is the equilibrium constant expression for the reaction H2 + I2 ⇌ 2HI?

Kc = [HI]² / ([H2][I2])

What does a large equilibrium constant (K >> 1) indicate about a reaction?

It indicates that the equilibrium favors the products.

According to Le Chatelier's Principle, how does a system at equilibrium respond to an increase in concentration of reactants?

The system will shift to the right, favoring the formation of products.

What happens to the equilibrium position when the pressure is increased in a reaction with fewer moles of gas on one side?

The equilibrium will shift towards the side with fewer moles of gas.

Define the reaction quotient (Qc).

Qc allows us to determine the direction of a reaction given initial or current concentrations.

When is the reaction at equilibrium in relation to Qc and Kc?

When Qc = Kc, the reaction is at equilibrium.

What is the effect of adding a catalyst to a chemical reaction at equilibrium?

Adding a catalyst lowers the activation energy but does not change the equilibrium constant or position.

How does increasing temperature affect the equilibrium of an endothermic reaction?

Increasing temperature favors the endothermic process.

What happens to the equilibrium position when you add a pure solid to the reaction mixture?

Adding a pure solid does not change the equilibrium position since its concentration does not change.

What does Kp stand for in relation to Kc?

Kp represents the equilibrium constant in terms of partial pressures, while Kc represents the equilibrium constant in terms of molarity.

What is the general formula for writing the equilibrium constant expression for a reaction aA + bB ⇌ cC + dD?

Kc = [C]ᶜ[D]ᵈ / [A]ᵇ[B]ᵃ

What does it mean if K < 1 for a reaction?

It indicates that the equilibrium favors the reactants.

What is the significance of using ICE tables in chemical equilibrium calculations?

ICE tables help organize initial concentrations, changes in concentrations, and equilibrium concentrations for solving equilibrium problems.