Metals and their uses Flashcards
Where are metals found?
In the earth’s crust
What are the main two methods of extracting metals?
Extraction by carbon
Electrolysis
Why is extraction by carbon limited?
It only works on metals less reactive than itself
What are the two steps to electrolysis?
- Melt the ore
2. Use lots of electricity
Why is electrolysis expensive?
It uses a lot of electricity
Give two modern day problems with copper
- Copper rich ores are running out
2. Environmental issues
Give three properties of copper
- Ductile (Can be shaped)
- Very unreactive (Good for water pipes)
- Good electrical conductor (Good for wires)
What is smelting?
Heating crushed ore
List two modern ways of extracting copper
- Phytomining
2. Bioleaching
How is phytomining done? (3 marks)
- Plants absorb copper ions
- The plants are burned and the metals can be extracted from the ash by adding sulphuric acid
- Then we use displacement by scrap iron and electrolysis to extract the copper.
How is bioleaching done?
- Bacteria feeds on low grade metal ores
- By a combination of biological and chemical processes
- Then scrap iron and electrolysis is used to extract the copper
In general give three properties of transition metals.
- Strong
- Can be bent (malleable)
- Good conductors of electricity
What alloy did copper and tin make?
Bronze
What alloy did copper and zinc make?
Brass
Does Aluminium have a low or high density?
Low
