Unit 3 OAS1

• Fuel Cell

  • Non-rechargeable and involve a conversion of chemical energy to electrical energy
• Fuel Cell

  • Reactant continuously supplied and products continuously excreted.
• Fuel Cells

  • More Efficient
• Fuel Cells

  • Electrodes are porous
• Fuel Cells

  • Can be used to generate electricity de novo
• Galvanic Cell

  • Non-rechargeable and involve a conversion of chemical energy to electrical energy
• Galvanic Cells

  • Less Efficient
• Galvanic Cells

  • Set amount of reactants and products
• Galvanic Cells

  • Electrodes are not usually porous
• Galvanic Cell

  • Less Effective at generating electricity, better for storing energy to be converted to electrical energy
• We use Fe3+ instead of Fe2+ because we use electrode as a graphite(carbon). Graphite is an inert electron and does not react with the ions metal in the solution which allows the focus of the redox reaction to be on the iron ions without interference from the electrode material.
• What is the purpose of using salt bridge in Galvanic cell

  • The purpose of  salt bridge in galvanic cell is to maintain electrical neutrality.
• Redox reaction

  Involves the balanced transfer of electrons between chemical species
• Flow of ions

  1. Anion migrates to Anode and undergoes oxidation

  2. Cation migrates to Cathode and undergoes reduction
• Electrolytes


  Solutions containing ions that allow the flow of electric current between the anode and cathode
• Electrolytes


  • Typically consist of salts or acids dissolved in water
• Direct contact of reactants

  Chemical energy is converted into heat energy
• Separation of reactants as half cells

  They cannot directly exchange electrons that are transferred through the external circuit, so they'll produce electrical energy
• Fuel Cell Design


  • Porous electrodes are used to maximise efficiency of diffusion of gaseous reactants and to maximise the ability of catalysts
  • Catalyst Electrode is a conductor on both anode and cathode through electrochemical reaction
• Galvanic cell


  Non-rechargeable and involves a conversion of chemical energy from spontaneous redox reaction to electrical energy
• Fuel Cell


  Non-rechargeable and involves a conversion of chemical energy to electrical energy via a redox reaction