Potential Energy Diagrams and Reactions

This video tutorial explains potential energy diagrams, focusing on exothermic and endothermic reactions. It covers how to interpret these diagrams, including understanding the activated complex, activation energy, and enthalpy changes. The video also provides guidance on analyzing diagrams to determine reaction types and energy changes.

What is the term used in science to describe stored energy in substances?

• Thermal energy

• Potential energy

• Chemical energy

• Kinetic energy

In a potential energy diagram, what does a negative Delta H indicate?

• Equilibrium

• No reaction

• Exothermic reaction

• Endothermic reaction

What is the term for the highest point on a potential energy diagram?

• Reactants

• Products

• Activated complex

• Equilibrium point

How is the activation energy of a forward reaction determined?

• By dividing the energy of the activated complex by two

• By adding the energy of reactants and products

• By measuring the energy difference from reactants to the activated complex

• By subtracting the energy of products from reactants

In an endothermic reaction, how does the energy of products compare to reactants?

• Products have lower energy

• Products have higher energy

• Products have the same energy

• Energy cannot be determined

What is the Delta H value for an endothermic reaction starting at 50 kJ and ending at 100 kJ?

• 50 kJ

• -50 kJ

• 100 kJ

• -100 kJ

What does the arrow from reactants to the activated complex represent in a potential energy diagram?

• Potential energy of products

• Delta H of the reaction

• Activation energy of the forward reaction

• Potential energy of reactants

How can you determine if a reaction is exothermic using a potential energy diagram?

• Reactants and products have the same energy

• Products are higher in energy than reactants

• Reactants are higher in energy than products

• Energy levels are not shown

What does a positive Delta H indicate in a potential energy diagram?

• No reaction

• Equilibrium

• Endothermic reaction

• Exothermic reaction

In a potential energy diagram, what does the arrow from the x-axis to the top of the curve represent?

• Potential energy of the activated complex

• Potential energy of products

• Delta H of the reaction

• Potential energy of reactants