1.3 Metals and Their Uses Flashcards
What is an ore?
A rock that contains enough metal to make it economically viable to extract
What are the methods of extracting metals from ore?
Electrolysis, reduction with carbon, displacement reaction, bioleaching, phytomining
What happens to an ore when it is reduced?
Oxygen is removed from it
Which metals can be extracted via reduction with carbon?
Metals less reactive than carbon (zinc, iron, tin, copper)
Which metals have to be extracted via electrolysis?
Metals more reactive than carbon (potassium, sodium, calcium, magnesium, aluminium)
What happens to an ore when the metal is extracted by electrolysis?
The ions are seperated using electricity
Why does copper need to be purified?
The copper produced from reduction with carbon is impure and doesn’t conduct electricity very well
What is the positive electrode called?
Anode
What is the negative electrode called?
Cathode
What is needed to extract copper using a displacement reaction?
A metal more reactive than copper and a dissolved metal compound e.g copper sulfate
How does bioleaching work?
Using bacteria to break the bonds between copper and sulfur. The bacteria get energy from the bonds.
How does phytomining work?
Growing plants in soil that contains copper. The copper builds up in the leaves and can then be obtained by harvesting, drying and burning the plants.
Why is recycling metals important?
Mining and extracting metals uses lots of energy which uses fossil fuels, these are running out and cause global warming. Less energy means less money. Finite amount of metal. Less rubbish in landfill.
What are the basic properties of metals?
Strong, can be bent into shapes, conduct heat and electricity
What is an alloy?
Two metals bonded together
Why is cast iron not very useful?
Because it’s only 96% iron, the impurities make it brittle and because of the regular arrangement of atoms it is very soft and easily shaped
Why are alloys harder than pure metals?
Different metals have different sized atoms, this interrupts the regular layers making it harder for them to slide over each other
What are the different types of iron alloys?
Low carbon steel, high carbon steel, stainless steel
What is in low carbon steel, what properties does it have and what is it used for?
0.1% carbon, easily shaped, car bodies
What is in high carbon steel, what properties does it have and what is it used for?
1.5% carbon, very hard and inflexible, knife blades and bridges
What is in stainless steel, what properties does it have and what is it used for?
Chromium and sometimes nickel, corrosion-resistant, cutlery
Why is copper used in wires?
It is a very good conductor of electricity and it’s hard and strong yet bendy
What makes aluminium and titanium useful?
They have very low densities. Aluminium isn’t strong but it’s useful in alloys. Titanium is strong
