Exo/endothermic reactions

• Measuring the amount of energy in a chemical reaction is important as:

  • Measure the energy values of fuels
  • Calculate energy required for industrial processes
  • Can calculate the theoretical amount of energy needed to break and form bonds
  • Helps predict whether or not a reaction will take place
• Thermochemistry is the study of heat changes during chemical reactions
• When chemical reactions occur, energy is put in to break bonds and is given out when making bonds, overall energy will change
• Reactions that release more energy than taking in, are exothermic (exit of heat) (e.g. Respiration)

  Reactions that take in more energy than releasing, are endothermic (entry of heat) (e.g. Photosynthesis)