weak topics!!

• What must be supplied to break bonds?

  Energy
• What happens during a chemical reaction regarding bonds?

  Old bonds are broken and new bonds are formed
• Why is bond breaking considered an endothermic process?

  Because energy must be supplied to break bonds
• What is released when new bonds are formed?

  Energy
• What characterizes exothermic reactions?

  Energy released by forming bonds is greater
• What characterizes endothermic reactions?

  Energy used to break bonds is greater
• What do reaction profiles show?

  • Relative energies of reactants and products
  • Energy changes over the course of the reaction
• What does the difference in height on a reaction profile represent?

  The overall energy change in the reaction
• What does the initial rise in a reaction profile indicate?

  The energy needed to break old bonds
• What is activation energy?

  The minimum energy needed for reactants to collide
• How does a higher activation energy affect a reaction?

  More energy is needed to start the reaction
• What indicates an exothermic reaction in a reaction profile?

  Products are at a lower energy than reactants
• What indicates an endothermic reaction in a reaction profile?

  Products are at a higher energy level than reactants