Fuel cells

• What is the main focus of the video discussed in the study material?

  The hydrogen oxygen fuel cell and its pros and cons
• What is a fuel cell?

  A type of electrochemical cell that converts chemical energy into electrical energy
• What does a hydrogen oxygen fuel cell convert into electrical energy?

  The chemical energy of hydrogen and oxygen
• What is the most common type of fuel cell mentioned?

  The hydrogen oxygen fuel cell
• What is produced when hydrogen and oxygen react in a fuel cell?

  Water and electrical energy
• What is the structure of a hydrogen oxygen fuel cell?

  • Central electrolyte (common: potassium hydroxide)
  • Negative anode on the left
  • Positive cathode on the right
  • Connected by a wire for electron flow
  • Anode compartment (hydrogen inlet) and cathode compartment (oxygen inlet)
  • Outlet for water and heat
• What role does the electrolyte play in a fuel cell?

  It allows ions to move through it
• What is the common material used for the electrodes in fuel cells?

  Porous carbon
• What happens to hydrogen at the anode in a fuel cell?

  It is oxidized, losing electrons to become hydrogen ions
• What is the equation for the loss of electrons during hydrogen oxidation?

  Hydrogen atoms lose electrons to become hydrogen ions
• What do the electrons do after being released from the hydrogen at the anode?

  They pass around the wire to the cathode
• What do hydrogen ions do after being produced at the anode?

  They move through the electrolyte to the cathode
• What is required for the reaction at the cathode to occur?

  Hydrogen ions and electrons must react with oxygen
• How many hydrogen ions and electrons are needed to react with one oxygen molecule?

  Four hydrogen ions and four electrons
• What is produced at the cathode when hydrogen ions and electrons react with oxygen?

  Two molecules of water
• What are half equations in the context of fuel cells?

  Equations showing the loss or gain of electrons during oxidation and reduction
• What is the overall equation for the reaction in a hydrogen oxygen fuel cell?

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

  The potential difference created by the oxidation of fuel
• What are the pros and cons of hydrogen oxygen fuel cells?

  Pros:

  • Only require hydrogen and oxygen
  • Do not produce carbon dioxide or pollutants
  • Longer lifespan than batteries
  • Less polluting to dispose of

  
  

  Cons:

  • Hydrogen is a gas, requiring more storage space
  • Hydrogen is explosive when mixed with air
  • Producing hydrogen often requires energy from fossil fuels
• What is the main idea behind using fuel cells in vehicles?

  To replace fossil fuel engines and batteries that are polluting
• What is a significant disadvantage of storing hydrogen as a fuel?

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

  Because it is explosive when mixed with air
• What is the main problem associated with producing hydrogen fuel?

  It often requires energy from fossil fuels