Other Methods of Extracting Metals

Question 1

Describe the process of extracting a metal using electrolysis.

Answer 1

Once the metal ore has melted, an electric current can be passed through it - the metal is discharged at the cathode and the non-metal at the anode

Question 2

Give some reasons why electrolysis is an expensive method of extracting metals.

Answer 2

• Large amounts of electricity are required
• Costs associated with melting or dissolving the metal ore so that it can conduct electricity

Question 3

State one advantage of producing a metal by electrolysis.

Answer 3

The metal produced by electrolysis is very pure

Question 4

Name two biological methods of extracting metals.

Answer 4

• Bioleaching
• Phytoextraction

Question 5

Describe the process of bioleaching.

Answer 5

• Bacteria are used to separate metals from their ores - bacteria gain energy from bonds between atoms in ore, separating out metal from ore
• This produces a leachate solution containing metal ions that can be extracted

Question 6

Describe the process of phytoextraction.

Answer 6

• Plants are grown in soil containing metal compounds - the metals build up in the leaves of plants
• These plants can then be burned in a furnace - the ash contains metal compounds from which the metal can be extracted

Question 7

(Exam-style question)

Nickel is extracted from nickel compounds.

State one advantage of extracting nickel by phytoextraction rather than from its ore.

Answer 7

Any one from:

• It decontaminates the ground
• It conserves nickel / allows for use of low-grade ore
• There is less noise pollution that would be caused by mining
• It is carbon neutral / less carbon dioxide is produced

Question 8

Give one disadvantage of extracting a metal via phytoextraction.

Answer 8

It is a slow process, as you need to wait for the plant to grow