Potential Energy Diagrams and Reactions

This video tutorial explains potential energy diagrams, focusing on the combustion of methane. It covers how to identify reaction types as endothermic or exothermic by comparing reactant and product energies. The tutorial also details calculating activation energy and Delta H, illustrating the differences between exothermic and endothermic reactions. Key concepts include energy changes, activation energy, and the significance of Delta H in chemical reactions.

What is the primary focus of a potential energy diagram?

• To show the speed of a reaction

• To illustrate the energy changes during a reaction

• To display the color changes in a reaction

• To measure the pressure changes in a reaction

In a potential energy diagram, where are the reactants typically located?

• On the right side

• On the left side

• At the top

• At the bottom

How can you identify an exothermic reaction using a potential energy diagram?

• The reactants have less energy than the products

• The diagram forms a straight line

• The energy level goes uphill

• The reactants have more energy than the products

What is the energy of the reactants in the given example?

• 20 kilojoules

• 80 kilojoules

• 60 kilojoules

• 30 kilojoules

What does the activation energy represent in a reaction?

• The total energy of the products

• The energy of the reactants

• The energy required to start the reaction

• The energy lost during the reaction

How is activation energy calculated from a potential energy diagram?

• By dividing the energy of reactants by the energy of products

• By subtracting the energy of reactants from the peak energy

• By subtracting the energy of products from reactants

• By adding the energy of reactants and products

What does a negative Delta H indicate in a reaction?

• Energy is absorbed by the reaction

• Energy is released from the reaction

• The reaction is endothermic

• The reaction is at equilibrium

In an endothermic reaction, how does the activation energy compare to an exothermic reaction?

• It is smaller

• It is negligible

• It is larger

• It is the same

What does a positive Delta H signify in a reaction?

• Energy is released

• Energy is absorbed

• The reaction is exothermic

• The reaction is spontaneous

How is Delta H calculated in a potential energy diagram?

• By adding the energies of reactants and products

• By multiplying the energies of reactants and products

• By dividing the energy of products by reactants

• By subtracting the energy of reactants from products