metal extraction

• Why are most metals found in the Earth's crust?

  They are already reacted with other elements
• What is a significant metal mentioned in the material?

  Copper
• What is copper primarily used for?

  In electronic equipment such as phones
• What is the definition of a metal ore?

  A rock containing enough metal to extract
• What does the term 'economical' mean in this context?

  Cost-effective
• What is the problem with copper ores mentioned in the material?

  Copper ores are becoming scarce
• What are low-grade ores?

  Ores containing only a small amount of copper
• What is the first method of extracting copper mentioned?

  Phyto mining
• How do plants contribute to phyto mining?

  They absorb metal compounds and concentrate them
• What happens to the plants after they are harvested in phyto mining?

  They are burned to produce ash
• What does the ash contain after burning the plants in phyto mining?

  A relatively high concentration of metal compound
• What is the second method of extracting metals mentioned?

  Bio leaching
• How do bacteria assist in bio leaching?

  They carry out chemical reactions to produce leachate
• What is the solution produced in bio leaching called?

  Leachate
• What do both phyto mining and bio leaching achieve?

  Extraction of metal compounds from low-grade ores
• How can copper be extracted from its compounds?

  By displacing it using iron
• Why is scrap iron used for copper extraction?

  It is cheap
• What is another method to extract copper besides displacement?

  Electrolysis
• What are the key points about phyto mining and bio leaching?

  • Economically extract metals from low-grade ores
  • Do not involve large-scale digging or transporting rock