Equilibrium Constant Expression For Some Important Reactions

Overview

The equilibrium constant expression for some important reactions describes the relationship between the concentrations of reactants and products at equilibrium. It is derived from the law of mass action, which states that the ratio of the concentrations of the products to the concentrations of the reactants is constant at a given temperature. For example, in the formation of an ester from an organic acid and alcohol in the aqueous phase, the equilibrium constant expression can be formulated based on the balanced chemical equation, reflecting the concentrations of the involved species at equilibrium

Questions and Answers

  1. What does the equilibrium constant expression represent in a chemical reaction?

    The equilibrium constant expression represents the ratio of the concentrations of the products to the concentrations of the reactants at equilibrium, as defined by the law of mass action

  2. How are the coefficients of a balanced chemical equation represented in the equilibrium constant expression?

    The coefficients of the balanced equation appear as exponents of the terms of concentrations in the equilibrium constant expression

  3. What does a large equilibrium constant value indicate about a reaction?

    A large equilibrium constant value indicates that the reaction is almost complete, meaning that the products are favored at equilibrium

  4. In what phase does the formation of an ester from an organic acid and alcohol typically occur?

    The formation of an ester from an organic acid and alcohol typically occurs in the aqueous phase

  5. What happens to the equilibrium position if the concentration of reactants is increased?

    If the concentration of reactants is increased, the equilibrium position shifts to the right, favoring the formation of products

Multiple-Choice Questions

  1. What does the equilibrium constant expression relate?

    a) Temperature and pressure
    b) Concentrations of reactants and products
    c) Volume and mass
    d) Energy and entropy
    Answer: b) Concentrations of reactants and products

  2. In the equilibrium constant expression, the coefficients of the balanced equation appear as what?

    a) Multipliers
    b) Exponents
    c) Divisors
    d) Addends
    Answer: b) Exponents

  3. What does a large equilibrium constant indicate about a reaction?

    a) The reaction is incomplete
    b) The reaction is almost complete
    c) The reaction does not occur
    d) The reaction is at equilibrium
    Answer: b) The reaction is almost complete

  4. What happens to the equilibrium position if the concentration of reactants is increased?

    a) It shifts to the left
    b) It shifts to the right
    c) It remains unchanged
    d) It becomes undefined
    Answer: b) It shifts to the right

  5. Which of the following is true about the equilibrium constant at a given temperature?

    a) It changes with pressure
    b) It is specific and remains constant
    c) It is always equal to 1
    d) It varies with concentration
    Answer: b) It is specific and remains constant