Le Chatelier's Principle and Equilibrium Dynamics

This lesson introduces Le Chatelier's Principle, which describes how a system at equilibrium responds to stresses such as changes in concentration, pressure, and temperature. The principle is explained using analogies and hypothetical reactions. When concentration changes, equilibrium shifts to counteract the stress. In gaseous systems, pressure changes affect equilibrium by shifting it towards the side with fewer or more moles. The lesson concludes with a summary and a preview of the next topic on temperature effects.

What does Le Chatelier's Principle primarily explain?

• The energy changes in reactions

• The formation of new compounds

• The rate of chemical reactions

• How systems at equilibrium respond to external stresses

In the analogy of digging and refilling a hole, what happens if you dig faster than your friend refills?

• The hole disappears

• The hole gets larger

• The hole remains the same size

• The hole gets smaller

What happens to the equilibrium when more reactants are added to a system?

• Equilibrium is destroyed

• Equilibrium remains unchanged

• Equilibrium shifts to the right

• Equilibrium shifts to the left

If the concentration of products is decreased, which direction does the equilibrium shift?

• To the left

• It oscillates

• It remains unchanged

• To the right

How does an increase in pressure affect a gaseous equilibrium system?

• No effect on equilibrium

• Shifts to the side with fewer moles

• Shifts to the side with more moles

• Equilibrium is destroyed

In a reaction with 2 moles of reactant A and 3 moles of reactant B, which side will equilibrium favor if pressure is increased?

• The side with 2 moles

• The side with 4 moles

• The side with 5 moles

• The side with 3 moles

What happens to equilibrium when pressure is decreased in a gaseous system?

• Equilibrium is destroyed

• No effect on equilibrium

• Shifts to the side with fewer moles

• Shifts to the side with more moles

Which of the following is NOT a stress that affects equilibrium according to Le Chatelier's Principle?

• Change in pressure

• Change in color

• Change in temperature

• Change in concentration

What will be covered in the next lesson following this one?

• Changes in concentration

• Changes in pressure

• Changes in temperature

• Changes in volume

What is the main goal of a system at equilibrium when it is stressed?

• To form new products

• To restore equilibrium

• To decrease energy

• To increase the rate of reaction