Chemical Equilibrium Quantitative Aspects

What is the equilibrium constant expression for the reaction aA + bB ⇌ cC + dD?

• Kc = [A]^a[B]^b * [C]^c[D]^d

• Kc = [A]^a[B]^b + [C]^c[D]^d

• Kc = [A]^a[B]^b / [C]^c[D]^d

• Kc = [C]^c[D]^d / [A]^a[B]^b

How does the value of equilibrium constant Kc change with temperature?

• The value of equilibrium constant Kc is directly proportional to temperature

• The value of equilibrium constant Kc decreases with an increase in temperature and increases with a decrease in temperature

• The value of equilibrium constant Kc remains constant regardless of temperature changes

• The value of equilibrium constant Kc increases with an increase in temperature and decreases with a decrease in temperature.

Explain the concept of reaction quotient Q in chemical equilibrium.

• Q represents the total number of moles of reactants and products in a reaction

• The reaction quotient Q is a mathematical expression that relates the concentrations of products and reactants in a chemical reaction at any given time. It helps determine the direction in which a reaction will proceed towards equilibrium.

• The reaction quotient Q is a constant value that does not change during a reaction

• Q is only calculated at the beginning and end of a reaction

What is the significance of the reaction quotient Q compared to the equilibrium constant K?

• Q is only calculated at equilibrium

• Q is always greater than K in a reaction

• Q provides information about the reaction at any point, while K describes the reaction at equilibrium.

• Q and K have the same numerical value

How does the reaction quotient Q help determine the direction of a reaction?

• The reaction quotient Q is only used for calculating reaction rates

• The reaction quotient Q is always equal to the equilibrium constant K

• The reaction quotient Q helps determine the direction of a reaction by comparing it to the equilibrium constant K.

• The reaction quotient Q is not related to determining the direction of a reaction

Define Le Chatelier's Principle and how it applies to chemical equilibrium.

• Le Chatelier's Principle states that reactions always go to completion.

• Le Chatelier's Principle explains how chemical systems respond to changes in conditions to maintain equilibrium.

• Le Chatelier's Principle only applies to exothermic reactions.

• Le Chatelier's Principle does not affect equilibrium in chemical systems.

What factors can affect the equilibrium position of a reaction?

• pH, solubility, mass

• Volume, color, time

• Temperature, pressure, concentration, catalysts

• Surface area, viscosity, density

How does changing the pressure of a system at equilibrium affect the equilibrium position?

• The equilibrium position remains unchanged regardless of pressure changes.

• The equilibrium position shifts to counteract changes in pressure based on the number of moles of gas involved in the reaction.

• Increasing pressure always shifts the equilibrium position to the right.

• Decreasing pressure always shifts the equilibrium position to the left.

Explain the effect of adding a catalyst to a reaction at equilibrium.

• The reaction becomes irreversible

• The reaction rate decreases

• The equilibrium position shifts to the left

• The equilibrium position remains unchanged, but the reaction reaches equilibrium faster.

Calculate the equilibrium constant Kc for the reaction N2(g) + 3H2(g) ⇌ 2NH3(g) given the concentrations of reactants and products.

• Kc = ([NH3]^3) / ([N2] * [H2]^2)

• Kc = ([NH3]^2) / ([N2] + [H2]^3)

• Kc = ([NH3]^2) / ([N2] + [H2])

• Kc = ([NH3]^2) / ([N2] * [H2]^3)