extraction

• Why are most metals found as compounds?

  They have reacted with other elements.
• What must happen to extract metals from ores?

  Metals must be extracted from their compounds.
• What is used to extract metals less reactive than carbon?


  Carbon
• Why is carbon used for extraction of certain metals?

  It is cheap and abundant.
• What happens to metal oxides during reduction with carbon?

  They lose oxygen to form pure metal.
• How is reduction with carbon typically performed?

  By heating metal oxide with carbon.
• What is electrolysis used for in metal extraction?

  To extract reactive metals from molten ores.
• Which metals are typically extracted using electrolysis?

  Metals more reactive than carbon.
• What is formed at the anode during electrolysis?

  Carbon dioxide
• Why is carbon used for the anode in electrolysis?

  It is a good conductor and cheap.
• What is formed at the cathode during electrolysis?

  Aluminium
• What is a major disadvantage of electrolysis for metal extraction?

  It requires a lot of energy.
• What are the energy requirements for electrolysis?

  To melt ionic compounds and produce current.
• Why does the energy cost matter in electrolysis?

  It significantly increases the overall cost.