7.9: Introduction to Le Chatelier's Principle

Multiple Choice

The following factors affect the position of equilibrium EXCEPT

• Concentration
• Pressure
• Temperature
• States of matter

Multiple Choice

2SO_2(g)+O_2(g) ⇌ 2SO_3(g) + Heat

Adding SO_2(g) will

• shift equilibrium right

• shift equilibrium left

• increase rate of reaction

• have no change

Multiple Choice

2SO₂(g)+O₂(g) ⇌ 2SO₃(g) + Heat

Increasing the temperature will...

• shift equilibrium right

• shift equilibrium left

• increase pressure

• have no change

Multiple Choice

2SO₂(g)+1O₂(g) ⇌ 2SO₃(g) + Heat

Increasing the pressure on the system will...

• shift equilibrium right

• shift equilibrium left

• slow rate of reaction

• have no change

Possible Quiz Questions

Multiple Choice

When colorless solutions of Fe³⁺ and SCN^- are combined a deep red FeSCN²⁺ forms. Which of the following explains the observation that adding KSCN to the mix makes the red color deeper.

• The added KCN dissolves, disturbing the charge balance of the solution, causing Fe(SCN)3 to precipitate as a red solid.

• The added KSCN dissolves, causing the solution to become saturated in SCN- ions, which appear red in high concentrations.

• The added KSCN dissolves, causing the reaction system to respond by producing more product to partially consume SCN- and reduce its concentration.

• The added KSCN dissolves, causing the reaction system to respond by forming more Fe3+ ions, which have a deep orange color at high concentrations

Multiple Choice

Which predicts the effect that the addition of HNO₃ (aq) will have on the equilibrium shown in reaction 1, and why?

• The equilibrium of reaction 1 will shift toward the formation of more product, because N₂O₅ (g) is removed when it reacts to form HNO₃ (aq)

• The equilibrium of reaction 1 will shift toward the formation of more product, because H₂O (l) acts as a catalyst for reaction 1.

• The equilibrium of reaction 1 will shift toward the formation of more reactants, because the product N₂O₅ (g) is removed when it reacts to form HNO₃ (aq)

• The equilibrium of reaction 1 is not affected, because neither H₂O (l) nor HNO₃ (aq) are gases.