Fuel cells

• What is the focus of today's video?

  How hydrogen oxygen fuel cells work
• What is a fuel cell?

  A type of electrochemical cell
• What do fuel cells convert energy into?

  Electrical energy from chemical energy
• What is the most common type of fuel cell?

  Hydrogen oxygen fuel cell
• What do hydrogen and oxygen combine to form in a fuel cell?

  Water
• What is the role of the electrolyte in a fuel cell?

  Allows ions to move through
• What is one common type of electrolyte used?

  Potassium hydroxide
• What are the two electrodes in a fuel cell?

  Anode and cathode
• Which electrode is negative in a fuel cell?

  Anode
• What connects the anode and cathode in a fuel cell?

  A wire
• Why is the labeling of electrodes in fuel cells confusing?

  It is opposite to electrolysis
• What material are both electrodes made of?

  Porous carbon
• What is the purpose of the catalyst in the electrodes?

  To speed up the reaction
• Where does hydrogen enter the fuel cell?

  From the anode compartment
• Where does oxygen enter the fuel cell?

  From the cathode compartment
• What happens to water and heat after the reaction?

  They leave via the outlet
• What happens to hydrogen at the anode?

  It is oxidized
• What does hydrogen lose to become a hydrogen ion?

  An electron
• What do electrons do after being released by hydrogen?

  Pass around the wire to the cathode
• What do hydrogen ions do after being produced?

  Move through the electrolyte to the cathode
• What do hydrogen ions and electrons react with at the cathode?

  Oxygen
• How many hydrogen ions and electrons are needed for one oxygen molecule?

  Four hydrogen ions and four electrons
• What is produced when hydrogen ions and oxygen react?

  Two molecules of water
• What are the two half equations in the fuel cell reaction?

  Oxidation of hydrogen and reduction of oxygen
• What does the overall equation of the fuel cell show?

  Combining oxygen and hydrogen to make water
• What drives the electrons around the circuit in a fuel cell?

  The potential difference across the cell
• What is the main idea behind using fuel cells?

  To replace fossil fuel engines and batteries
• What is a major benefit of hydrogen oxygen fuel cells?

  They produce no carbon dioxide waste
• Why are hydrogen oxygen fuel cells considered simple devices?

  They last longer than batteries
• What is a downside of storing hydrogen?

  It takes up more space than fossil fuels
• Why is storing hydrogen considered dangerous?

  It is explosive when mixed with air
• What is a major problem with producing hydrogen fuel?

  It requires energy often from fossil fuels
• What should you mention about how fuel cells work in exams?

  Fuel enters the cell and becomes oxidized
• What does the term "oxidized" mean in the context of fuel cells?

  Hydrogen atoms lose electrons
• What does "potential difference" refer to in a fuel cell?

  Difference in charge between electrodes
• What are the pros and cons of hydrogen oxygen fuel cells?

  Pros:

  • Only require hydrogen and oxygen
  • No carbon dioxide or pollutants produced
  • Longer lifespan than batteries
  • Less polluting to dispose of

  
  

  Cons:

  • Hydrogen is a gas, takes more space
  • Explosive when mixed with air
  • Hydrogen production requires energy, often from fossil fuels