CC15: Heat energy changes and chemical reactions

Cards (4)

  • Give an example of an exothermic reaction
    Respiration:
    glucose + oxygen —> carbon dioxide + water
  • give an example of an endothermic reaction
    photosynthesis:
    carbon dioxide + water —> glucose + oxygen
  • what is an exothermic reaction?
    where energy is transferred from stores of energy in chemical bonds to the surroundings and the temperature of the surroundings increases
    energy is given out so reactants activation energy is higher than the products
    making bonds is exothermic
    e.g: combustion, neutralisation and displacement reactions
  • what is an endothermic reaction?
    energy is transferred from the surroundings to stores of energy in chemical bonds and the temperature of the surroundings decreases
    the activation energy of the products is higher than the activation energy of the reactants because energy is taken in
    bonds in the reactant molecules break
    e.g: photosynthesis and thermal decomposition