Equilibrium Practice

What is the reaction/equation for this K_c expression_

• 2N₂ + O₂ ⇌ 2NO

• N₂ + O₂ ⇌ NO

• NO ⇌ 2NO

• N₂ + O₂ ⇌ 2NO

The Kc expression for the reaction 2NH₃ ⇌ N₂ + 3H₂

• 
• 
• 
• 

An equilibrium constant, K_eq is defined as

• product concentrations - reactant concentrations

• reactant concentrations - product concentrations

• [reactant] / [product]

• [product] / [reactant]

Calculate Kc for the reaction 2HI_(g) —> H_2(g) + I_2(g) given that the concentrations of each species at equilibrium are as follows: [HI] = 0.85 mol/L, [I₂] = 0.60 mol/L, [H₂] = 0.27mol/L.

• 0.19

• 0.22

• 4.5

• 5.25

• 160

Around what time does the reaction reach equilibrium?

• 25 min

• 70 min

• 45 min

• 80 min

The following reaction :

SO_{2 (g)} + NO_{2 (g)} ⇌ SO_{3 (g)} + NO (g)

established equilibrium and was found to contain

0.40 M SO₃ , 0.30 M NO,

0.15 M NO₂ , and 0.20 M SO₂.

Calculate the equilibrium constant for this reaction.

• 4.0

• .42

• .25

• 1.0

Use the reaction below to answer question:

N₂O₄(g) ⇌ 2NO₂ (g) ΔH = +92 KJ

Which way will the reaction shift if heat is added?

• Left

• Right

• No shift

heat + 2SO₂(g) + O₂(g) ⇌ 2SO₃(g)
decreasing the pressure will ...

• shift equilibrium towards products

• shift equilibrium towards reactants

• decrease the temperature

• have no change

A mixture of 0.10 mol of NO, 0.050 mol of H₂, and 0.10 mol of H₂O is placed into a 1.0-L vessel at 300 K.

At equilibrium, [NO] = 0.062 M.

Set up a RICE table.

Determine the equilibrium concentrations of H₂, N₂, and H₂O, then determine Kc.

2 NO_(g) + 2 H_2(g) ⇄ N_2(g) + 2 H₂O_(g)

• Kc = 650

• Kc = 3.58

• Kc = 0.501

• Kc = 50.

A very high value for K indicates that at equilibrium...

• reactants are favored.

• products are favored.

• equilibrium is reached slowly.

• equilibrium has been reached