Question 1

Consider the following equilibrium mixture in a closed system: H₂Og) + COg) ⇌ H₂g) + CO₂g). Explain what would happen to the equilibrium upon the addition of carbon monoxide gas? Outcome # 3) DOK 3)

A) The addition of carbon monoxide gas would disrupt the equilibrium causing it to shift towards the left which would result in more reactants being produced until equilibrium is achieved.
B) The addition of carbon monoxide gas would not disrupt the equilibrium, so nothing would happen.
C) The addition of carbon monoxide gas would disrupt the equilibrium causing it to shift towards the right which would result in more products being produced until equilibrium is achieved.

Accepted Answer

Adding carbon monoxide (CO) to the system increases the concentration of one of the reactants. According to Le Chatelier's principle, the system will respond by shifting the equilibrium to the right to consume the added CO, thus producing more products until a new equilibrium is established.

Question 2

Consider the following equilibrium mixture in a closed system: H₂Og) + COg) ⇌ H₂g) + CO₂g). Explain what would happen to the equilibrium upon the addition of carbon monoxide gas? Outcome # 3) DOK 3)

A) The addition of carbon monoxide gas would disrupt the equilibrium causing it to shift towards the left which would result in more reactants being produced until equilibrium is achieved.
B) The addition of carbon monoxide gas would not disrupt the equilibrium, so nothing would happen.
C) The addition of carbon monoxide gas would disrupt the equilibrium causing it to shift towards the right which would result in more products being produced until equilibrium is achieved.

Accepted Answer

The addition of hydrogen gas increases the concentration of one of the products, causing the equilibrium to shift to the left to counteract this change, resulting in the formation of more reactants.

Question 3

If the reaction quotient is greater than the equilibrium constant, which statement would be correct? Outcome # 4) DOK 1)&#10;A) If Q > K, then the reaction needs to proceed towards the right to reach equilibrium.&#10;B) If Q > K, then the reaction needs to proceed towards the left to reach equilibrium.&#10;C) If Q > K, then the reaction is at equilibrium.

Accepted Answer

When the reaction quotient (Q) is greater than the equilibrium constant (K), it indicates that there are more products relative to reactants than at equilibrium. Therefore, the reaction will shift towards the reactants (to the left) to reach equilibrium.

Question 4

Write the equilibrium expression for H₂Og) + COg) ⇌ H₂g) + CO₂g). Outcome # 3) DOK 1) A) K_c= [CO₂] [H₂] / [H₂O] [CO] B) K_c= [H₂O] [CO] / [CO₂] [H₂] C) K_c= [CO₂] [H₂] / [CO]

Accepted Answer

The equilibrium expression for a reaction is written as the product of the concentrations of the products raised to their stoichiometric coefficients, divided by the product of the concentrations of the reactants raised to their stoichiometric coefficients. In this case, the correct expression is [COS][H2O]/[H2][CO], which matches choice A.

Question 5

The K_c for the formation of HI from iodine and hydrogen gas is 54. If the concentrations of HI, I₂, and H₂ are 0.338 M, 0.112 M, and 0.198 M respectively, which statement is correct? Outcome # 4) DOK 2)

A) Q = 5.15 which is less than K_c, therefore the reaction needs to proceed towards the right to reach equilibrium
B) Q = 15.2 which is less than K_c, therefore the reaction needs to proceed towards the right to reach equilibrium
C) Q = 0.194 which is less than K_c, therefore the reaction needs to proceed towards the right to reach equilibrium

Accepted Answer

The reaction quotient Q is calculated using the formula Q = [HI]^2 / ([I2] * [H2]), substituting the given concentrations gives Q = (0.338)^2 / (0.112 * 0.198) = 5.15. Since Q < Kc (54), the reaction will proceed to the right to reach equilibrium.

Question 6

Write the equilibrium expression for 2NOg) + 2H₂g) ⇌ N₂g) + 2H₂Og). Outcome # 3) DOK 1) A) K_c= [NO]² [H₂]²/ [H₂O]² [N₂] B) K_c= [H₂O]² [N₂] / [NO]² [H₂]² C) K_c= [N₂] / [NO]² [H₂]²

Accepted Answer

The equilibrium expression is written as the product of the concentrations of the products raised to their stoichiometric coefficients divided by the product of the concentrations of the reactants raised to their stoichiometric coefficients.

Question 7

If the reaction quotient is less than the equilibrium constant, which statement would be correct? Outcome # 4) DOK 1)&#10;A) If Q < K, then the reaction needs to proceed towards the left to reach equilibrium.&#10;B) If Q < K, then the reaction is at equilibrium.&#10;C) If Q < K, then the reaction needs to proceed towards the right to reach equilibrium.

Accepted Answer

When the reaction quotient (Q) is less than the equilibrium constant (K), it indicates that there are not enough products relative to reactants. Therefore, the reaction will proceed in the forward direction (towards the right) to produce more products and reach equilibrium.

Deck 13: Fundamental Equilibrium Concepts