Chemistry 1

• Electrolysis


  The decomposition of an ionic compound when molten or in Aqua Solution by the passage of an electric current
• Electrolysis


  • Ionic compound should be either melted or in water so that they have free ions in order to allow electricity to pass through
• Electrode


  A conductor, often a metal or graphite Rod, that allows electric current to go in or out of an electrolyte
• Electrolyte


  The molten or aquous substance that undergoes electrolysis
• Molten


  Heated until it becomes a liquid
• Aquous


  Dissolved in water
• Cation


  A positively charged ion formed when an atom loses electrons
• Anion


  A negatively charged ion formed when an atom gains electrons
• Cathode


  The negative electrode that attracts positively charged cations
• Anode


  The positive electrode that attracts negatively charged anions
• Electrolysis


  1. Electric current flows through the circuit

  2. Electrons move from power supply to cathode making it negatively charged

  3. Anode becomes positively charged as it loses electrons

  4. Positive cations in electrolyte move towards cathode and gain electrons

  5. Negative anions in electrolyte move towards anode and lose electrons

  6. Electrons from anode move back to power supply
• In the electrolyte, it is the ions that move and carry the electrical charge when the current flows
• Oxidation


  Negative ions lose electrons at the anode
• Reduction


  Positive ions gain electrons at the cathode
• Electrolysis of molten sodium chloride

  1. At anode: 2 chloride ions lose 2 electrons to form Cl2 gas

  2. At cathode: Sodium ions gain 1 electron to form sodium