Extracting Metals Flashcards
What is a metal ore?
A rock containing enough metal to make it worthwhile extracting
What are the two methods of extracting metal?
Reduction
Electrolysis
What metals are extracted by electrolysis?
Any above carbon
How are metals between carbon and hydrogen extracted?
Carbon reduction (blast furnace)
Why is copper extracted by electrolysis?
To get the copper really pure
What metals aren’t extracted?
Silver gold and platinum
They are found native
What is a disadvantage of electrolysis?
Requires a lot of energy
What is an advantage of electrolysis?
You get a pure product
Where is the pure metal formed in electrolysis?
At the negative electrode (cathode)
How do metals more reactive than carbon have to be extracted?
Using electrolysis of molten compounds
Why is electrolysis expensive?
The heat require to melt the metal oxide used a lot of energy
How is electrolysis used to get copper?
Electrons are pulled off copper atoms at anode becoming Cu2+ ions, when they’re near the cathode they gain electrons and become copper atoms
What is the liquid for electrolysis called?
Electrolyte
How does the electrolyte conduct electricity?
Electrolyte has free ions which conduct electricity
Explain the process of bioleaching
Bacteria gets energy from bond between sulfur and copper and separates copper from ore in the process
How do we get the copper from bioleaching?
Once the copper has been extracted from its ore solution called leachate is left and it contains copper which is obtained through filtering
What is phytomining used for?
Extract copper from low grade ores (low % of carbon)
Explain the process of phytomining
Plants in ground absorb copper from soil
Plants harvested and burned
Ashes contain copper
Electrolysis used to extract
Give an advantage of phytomining and bioleaching
Cheap
Easy
Give a disadvantage of extracting copper by phytomining or bioleaching
Takes ages
Doesn’t give much copper
How is copper extracted by reduction with carbon?
It’s heated in a furnace (otherwise know as smelting)
Why don’t we extract copper by carbon reduction?
Copper produced is very impure
Impure copper doesn’t conduct electricity
Copper is used to make electrical wiring
Why is metal extraction good for the environment?
Useful products can be made
Provides jobs
Bring money to area (can afford transport and healthcare)
Why can metal extraction be bad for the environment?
Creates a lot of noise
Ruins landscape
Loss of habitats
Deep mine shafts can be dangerous
