Catalysts and Reaction Dynamics

The lecture discusses the role of catalysts in chemical reactions, focusing on their effect on equilibrium and reaction rates. Using the example of sulfur dioxide reacting with oxygen, it explains how catalysts speed up both forward and backward reactions by lowering activation energy, without shifting the equilibrium position. The net quantities of reactants and products remain unchanged, even though the reaction rates increase.

In the context of the lecture, what is the significance of the contact process?

• It is a method to slow down reactions

• It is an example of a reaction where a catalyst is used

• It is a method to change the equilibrium position

• It is a process to increase reactant concentration

What is the primary role of a catalyst in a chemical reaction?

• To increase the temperature of the reaction

• To decrease the concentration of reactants

• To speed up the reaction by lowering activation energy

• To change the equilibrium position

What is the effect of a catalyst on the activation energy of a reaction?

• It decreases the activation energy

• It increases the activation energy

• It has no effect on activation energy

• It doubles the activation energy

What is the effect of a catalyst on the speed of a reaction?

• It has no effect on the reaction speed

• It slows down the reaction

• It stops the reaction

• It speeds up the reaction

What is the role of activation energy in a chemical reaction?

• It is the energy required to stop a reaction

• It is the energy required to start a reaction

• It is the energy that decreases the reaction rate

• It is the energy that increases the reaction rate

In the given reaction, what happens to the rate of the forward and backward reactions when a catalyst is added?

• Both reactions slow down

• Only the backward reaction speeds up

• Only the forward reaction speeds up

• Both reactions speed up equally

How does a catalyst affect the equilibrium position of a reaction?

• It does not affect the equilibrium position

• It shifts the equilibrium to the left

• It stops the reaction

• It shifts the equilibrium to the right

Why does a catalyst not favor any side of a reaction at equilibrium?

• Because it speeds up both reactions equally

• Because it only affects the backward reaction

• Because it changes the concentration of reactants

• Because it only affects the forward reaction

If a catalyst is added to a reaction at equilibrium, what happens to the net quantities of reactants and products?

• The reaction stops

• The net quantities remain the same

• The net quantities of products increase

• The net quantities of reactants increase

What happens to the number of molecules produced per second when a catalyst is added to a reaction at equilibrium?

• The number of molecules produced decreases

• The number of molecules produced remains the same

• The number of molecules produced increases

• The reaction stops