Equilibrium and Le Chatelier's Principle

This video tutorial covers the effect of changing concentration on reversible reactions at equilibrium, specifically for higher-tier students. It begins with an introduction to reversible reactions and equilibrium, followed by an explanation of Le Chatelier's Principle. The video then explores how changes in concentration affect equilibrium, using the reaction between NO2 and N2O4 as an example. Practice questions are provided to reinforce understanding, and the video concludes with additional resources for further practice.

What is the main focus of this video lesson?

• Understanding the effect of temperature on reactions

• Learning about irreversible reactions

• Exploring the history of chemical reactions

• Describing the effect of concentration changes on equilibrium

What happens to a reversible reaction in a sealed container?

• Only the forward reaction occurs

• Equilibrium is achieved when forward and reverse reactions occur at the same rate

• The reaction stops completely

• Reactants and products escape

What principle explains how a system at equilibrium responds to changes?

• Avogadro's Principle

• Newton's Law

• Le Chatelier's Principle

• Boyle's Law

In the reaction between NO2 and N2O4, what happens if the concentration of NO2 is increased?

• The reaction stops

• More NO2 is formed

• More N2O4 is formed

• The concentration of NO2 remains the same

What is the effect of decreasing the concentration of N2O4 in the reaction?

• The concentration of N2O4 will increase

• The reaction will stop

• More NO2 will react to form N2O4

• No change will occur

If the concentration of N2O4 is increased, what is the expected outcome?

• The concentration of N2O4 will remain constant

• The reaction will stop

• No change will occur

• More NO2 will be formed

What is the result of increasing the concentration of a reactant in a system at equilibrium?

• The system remains unchanged

• The system shifts to produce more products

• The system shifts to produce more reactants

• The reaction stops

What is the primary goal of Le Chatelier's Principle?

• To stop the reaction

• To maintain equilibrium by counteracting changes

• To decrease the rate of reaction

• To increase the rate of reaction

What happens to the concentrations of substances when equilibrium is disturbed?

• They remain constant

• They change until a new equilibrium is reached

• They decrease to zero

• They increase indefinitely

What is the effect of adding more NO2 to the system at equilibrium?

• The concentration of NO2 decreases

• No change occurs

• The concentration of N2O4 increases

• The reaction stops