5.1.2 Equilibrium constants

• The equilibrium constant K is expressed as the ratio of product concentrations to reactant concentrations, each raised to their stoichiometric coefficients
• Match the type of equilibrium constant with its measurement unit:

  Kc ↔️ mol/L

  Kp ↔️ Pa
• Match the equilibrium constant with its primary use case:

  Kc ↔️ Reactions in solution

  Kp ↔️ Reactions involving gases
• What does a Kc value greater than 1 indicate about the reaction?

  Products are favored
• At equilibrium, the forward and reverse reaction rates are equal.

  True
• At equilibrium, the rates of the forward and reverse reactions are equal.


  True
• The equilibrium constant K_p uses partial pressures
• What does the equilibrium constant K quantify in a chemical reaction?

  Balance at equilibrium
• Match the equilibrium constant with its use case:

  K_c ↔️ Reactions in solution

  K_p ↔️ Reactions involving gases
• What does a K_c value greater than 1 indicate about the reaction?

  Products are favored
• What does K_p use instead of molar concentrations?

  Partial pressures
• Arrange the following key differences between K_c and K_p:

  1️⃣ K_c uses molar concentrations

  2️⃣ K_p uses partial pressures

  3️⃣ K_c is for reactions in solution

  4️⃣ K_p is for reactions involving gases
• The relationship between K_c and K_p is given by the formula: K_p = K_c (RT)Δn
• How is Δn calculated in the relationship between K_c and K_p?

  (moles of gaseous products) - (moles of gaseous reactants)
• K_c is measured in mol/L
• For which type of reactions is K_c most commonly used?

  Reactions in solution
• What is the value of the ideal gas constant R?

  8.314 J/(mol·K)
• What are the two main types of equilibrium constants?

  K_c and K_p
• If K_c > 1, the products are favored.


  True
• What does K_p use instead of molar concentrations?

  Partial pressures
• Match the equilibrium constant with its unit of measurement and use case:

  K_c ↔️ mol/L; Reactions in solution

  K_p ↔️ Pa, kPa, atm; Reactions involving gases
• For the reaction N₂(g) + 3H₂(g) ⇌ 2NH₃(g) at T = 298 K, if K_c = 0.01, then K_p ≈ 1.64 × 10⁻⁷
• What is the formula relating K_p and K_c?

  $K_{p} =$$K_{c}(RT)^{\Delta n}$
• What is the formula for calculating K_c from equilibrium concentrations?

  $K_{c} =$ \frac{[C]^{c} * [D]^{d}}{[A]^{a} * [B]^{b}}
• If K_c and the temperature are known, K_p can be calculated using the relationship K_p = K_c(RT)^Δn


  True
• What does it mean if the equilibrium constant K is less than 1?

  The reaction favors reactants
• What is the formula to convert between K_c and K_p?

  $K_{p} =$$K_{c} (RT)^{\Delta n}$
• For an endothermic reaction, increasing the temperature shifts the equilibrium to the product
• Arrange the steps in the process of determining how pressure changes affect gas-phase equilibria:

  1️⃣ Increase or decrease pressure

  2️⃣ Shift equilibrium to side with fewer gas moles

  3️⃣ Equilibrium constant K remains constant
• What does the equilibrium constant K quantify at equilibrium?

  Balance between reactants and products
• At equilibrium, the forward and reverse reaction rates are equal.


  True
• Kc uses molar concentrations, while Kp uses partial pressures.
• The equilibrium constant K is temperature-dependent.


  True
• Kc is the ratio of product concentrations to reactant concentrations at equilibrium.
• Order the steps for calculating Kc from equilibrium concentrations:

  1️⃣ Write the balanced chemical equation

  2️⃣ Determine the stoichiometric coefficients

  3️⃣ Measure equilibrium concentrations

  4️⃣ Calculate the ratio of product to reactant concentrations
• What is the formula for the equilibrium constant K in terms of concentrations for a generic reaction?

  $K =$ \frac{[C]^{c} * [D]^{d}}{[A]^{a} * [B]^{b}}
• The equilibrium constant K_c uses molar concentrations
• Match the equilibrium constant with its unit of measurement:

  K_c ↔️ mol/L

  K_p ↔️ Pa, kPa, atm
• At equilibrium, the rates of the forward and reverse reactions are equal.


  True
• K_c is the ratio of product concentrations to reactant concentrations at equilibrium