Energy and chemical change

Annotations:

• energy cannot be created or destroyed it can only change form
• there are two main types of chemical reactions
• energy changes occur during chemical reaction

1. endothermic reaction
   1. a reaction in which energy is absorbed
      1. change in enthalpy is negative
      2. an example of this is respiration
         1. this is the process through which cells obtain energy from organic compounds
         2. another example is combustion of fuels