Exothermic and Endothermic Reactions

• What is meant by an exothermic reaction?

  An exothermic reaction transfers energy from the reacting molecules to the surroundings.
• How does an exothermic reaction affect the temperature of the surroundings?

  The temperature of the surroundings increases, making them hotter.
• What is a common example of an exothermic reaction?

  Combustion, such as wood burning.
• Name two other examples of exothermic reactions.

  Certain oxidation reactions and neutralization reactions.
• What does an energy profile diagram represent in exothermic reactions?

  • The products have less energy than the reactants.
  • Energy is transferred from the reaction to the surroundings.
  • The difference in energy indicates the energy released.
• What are two practical uses of exothermic reactions?

  Hand warmers and self-heating cans.
• What is meant by an endothermic reaction?

  An endothermic reaction takes in energy from its surroundings.
• How does an endothermic reaction affect the temperature of the surroundings?

  The temperature of the surroundings decreases, making them colder.
• What is a good example of an endothermic reaction?

  Thermal decomposition.
• What does an energy profile diagram represent in endothermic reactions?

  • The products have more energy than the reactants.
  • Energy is taken in from the surroundings.
  • The difference in energy indicates the energy absorbed.
• What do exothermic and endothermic reactions have in common regarding energy profiles?

  Both have a peak representing the activation energy.
• What is activation energy?

  The minimum amount of energy that particles must have in order to react.
• How is activation energy represented on an energy profile diagram?

  It is the energy from the reactants to the peak of the curve.
• How can you identify activation energy on energy profiles for exothermic and endothermic reactions?

  • On exothermic profiles: from reactants to peak.
  • On endothermic profiles: from reactants to peak.
• Where can you find more questions on exothermic and endothermic reactions?

  In the revision workbook linked in the video.