Getting Metals From Rocks Flashcards
What is a metal ore
A rock containing enough metal to make it worthwhile extracting the metal from it
If the market price of a metal drops is it worth extracting it
No
If the market price of the ,teal increases is it worth extracting
Yes
How are metals extracted from an ore (2)
Reduction
Electrolysis
Why do some ores have to be concentrated before the material is extracted
Get rid of unwanted material
What else can electrolysis be used for as well as extracting metals from ores
Purify metals
How are metals extracted from ores via reduction
Use carbon
What happens when an ore is reduced
Oxygen is removed from it
How do you know whether s metal in extracted by electrolysis or reduction by carbon
If it is above carbon in the reactivity series them it is electrolysis(more reactive that carbon). If it is under carbon it is reduction by carbon (less reactive than carbon)
Why is electrolysis more expensive than reduction with carbon
Uses more energy
What metal is purified by electrolysis
Copper
How is copper extracted by reduction with carbon
Smelting
What is smelting
The ore being heated in a furnace
What is the disadvantage of extracting copper by smelting
It is impure meaning it doesn’t conduct electricity
Not useful because copper is used for electrical wiring
Why is electrolysis used to purify copper
Because it is impure once it has been extracted via smelting
What is electrolysis
Breaking down a substance using electrolysis
What is the electrolyte
A liquid to conduct the electricity
Explain how electrolysis is used to purify copper
1) The electrons are pulled off copper atoms at the anode (+)causing them to go into solution as Cu2+ ions
2) Cu2+ ions near the cathode(-) gain electrons and turn back into copper atoms
3) The impurities are dropped at the anode (+) whilst pure copper atoms bond to the cathode (-)
What is the displacement reaction for extracting copper
Copper sulfate + iron -> iron sulfate + copper
Why is it important to recycle copper
The copper-rich ores are limited and the demand for copper is growing
What are the two new methods for extracting copper from low percentage ores
Phytomining
Bio leaching
What does bio leach use to extract copper for low percentage ores
Bacteria
Explain the steps of bio leaching
1 The bacteria get their energy from the bond between copper and sulfur, separating copper from ore in the process
2 The leachate contains copper which can be extracted
What does phytomining use to extract copper
Plants
