electrolysis chem p1

• Electrolysis


  The breakdown of a substance using electricity
• Electrolysis


  Electrical energy from a direct current supply decomposes electrolytes
• Electrolysis involves electrodes, a current and an electrolyte
• Electrolyte


  A molten or dissolved ionic compound that conducts electricity
• The electrolyte has to be a liquid so that the ions are free to move
• During electrolysis


  Ions move to the electrodes
• Electrode


  A solid that conducts electricity
• Electrodes


  • They must be inert (unreactive), so they don't react with the electrolyte
• Anode


  The positive electrode
• Cathode


  The negative electrode
• During electrolysis


  1. Positively charged ions (cations) are attracted to the cathode and gain electrons

  2. Negatively charged ions (anions) are attracted to the anode and lose electrons
• Metals form positive ions, so they're attracted to the cathode
• When a pure metal forms at the cathode, it either sticks to the cathode or sinks
• Non-metals form negative ions, so they're attracted to the anode