5.3 Dynamic Equilibria and Calculations Involving Gases

• Why is there no net change in concentrations in dynamic equilibrium?

  Forward and reverse rates are equal
• The forward and reverse reactions in dynamic equilibrium proceed at the same speed.


  True
• Order the factors affecting dynamic equilibrium in terms of their primary effects on the system:

  1️⃣ Concentration: Shifts based on addition or removal of reactants/products

  2️⃣ Pressure: Affects gas equilibria with differing molecule counts

  3️⃣ Temperature: Favors exothermic or endothermic reactions
• Dynamic equilibrium occurs in a closed
• In a closed system, reactants or products can enter or leave.

  False
• In dynamic equilibrium, the forward and reverse reactions proceed at the same speed.
• What happens to the equilibrium when more reactants are added to the system?

  Shifts towards products
• In the Haber process, decreasing temperature favors ammonia formation because the reaction is exothermic.


  True
• The equilibrium constant $K_{p}$ is defined as the ratio of the partial pressures of the products raised to their stoichiometric coefficients
• A high $K_{p}$ indicates that the equilibrium favors the products.


  True
• Dynamic equilibrium is a state in a closed system where the rate of the forward reaction equals the rate of the reverse
• Dynamic equilibrium results in no net change in the concentrations of reactants and products over time.


  True
• Static equilibrium involves irreversible reactions.


  True
• For dynamic equilibrium, the system must be closed
• In dynamic equilibrium, the forward and reverse reaction rates must be equal
• Dynamic equilibrium involves reversible reactions, while static equilibrium involves irreversible reactions.

  True
• What is the term for a system where no substances can enter or leave?

  Closed system
• Increasing the concentration of reactants shifts the equilibrium towards products
• Which type of reaction is favored by increasing temperature?

  Endothermic reaction
• Dynamic equilibrium occurs in a closed system.
• Dynamic equilibrium results in no net change in concentrations over time.


  True
• In static equilibrium, concentrations remain constant because reactions are reversible.

  False
• Which type of reaction is favored by increasing temperature?

  Endothermic
• How is $K_{p}$ calculated for the reaction $aA +$$bB \rightleftharpoons cC +$$dD$?


  $K_{p} =$$\frac{(p_{C})^{c}(p_{D})^{d}}{(p_{A})^{a}(p_{B})^{b}}$
• The relationship between $K_{p}$ and $K_{c}$ is given by the expression K_{p} = K_{c}(RT)^{\Delta n}</latex>, where $\Delta n$ is the change in the number of moles of gas
• Match the term with its definition:

  Partial pressure ↔️ Pressure exerted by a specific gas

  Dalton's law ↔️ p_i = x_i × P

  Mole fraction ↔️ Ratio of moles of a gas to total moles
• Dynamic equilibrium is a state in a closed system where the rate of the forward reaction equals the rate of the reverse reaction.
• What happens to the reactions in static equilibrium?

  Reactions cease
• Pressure affects dynamic equilibrium only if gases are involved and the number of gas molecules differs on each side.
• The equilibrium constant $K_{p}$ is defined as the ratio of the partial pressures of products to reactants at equilibrium.


  True
• What is the defining characteristic of dynamic equilibrium in a closed system?

  Equal forward and reverse rates
• In dynamic equilibrium, the forward and reverse reactions proceed at the same rate.

  True
• What happens to reaction rates in static equilibrium?

  Reactions cease entirely
• In dynamic equilibrium, forward and reverse reaction rates must be equal
• What is an example of a dynamic equilibrium process used in industry?

  Haber process
• Increasing pressure in a gas equilibrium favors the side with more gas molecules.

  False
• What is dynamic equilibrium in a closed system?

  Equal forward and reverse rates
• Match the features with the type of equilibrium:

  Equal forward and reverse rates ↔️ Dynamic Equilibrium

  Reactions cease ↔️ Static Equilibrium
• What happens to concentrations in dynamic equilibrium once it is achieved?

  Remain constant
• Increasing pressure in a system with gases favors the side with fewer gas molecules.