16 terms

C1 - Topic 4: Obtaining and using metals

Explain why the method used to extract a metal is related to it's position in the reactivity series and the cost of the extraction process.
If a metal is unreactive, such as gold, it is usually found as it is and so can be extracted using a hammer and chisel. This means extraction is very cheap. The more reactive a metal, the more difficult it is to extract it so it's more expensive to do.
What three ways are used to extract a metal from it's ore?
-Hammer and chisel for extracting gold
-Displacement reaction using carbon. This only works though if the metal is below carbon in the reactivity series.
-Electrolysis is used if the metal is above carbon in the reactivity series.
What is an ore?
A rock containing enough metal to be worth extracting.
What is it called when a metal loses or gains oxygen?
Gains oxygen: oxidised
Loses oxygen: reduced
What happens when a metal is oxidised?
Which is the ONLY metal that rusts?
How does the position of a metal in the reactivity series relate to to it's resistance to oxidation?
The more reactive a metal, the less resistant it is to oxidation.
What are the typical properties of metals?
They are STRONG, but can be bent or hammered into different shapes.
Name 2 uses for aluminium (when used in an alloy), copper and gold
(accept any of the following)
window frames, aircraft, electricity cables.
electrical wires,pipes,plumbing
jewellery, tooth fillings, electric circuits
Why should we recycle?
(need at least 3)
-Preserves natural resources
-uses less energy, as we don't need to extract metals from ores
-reduces mining, which damages the environment
-less transport of waste and landfill
-produces less pollution as sulphur is extracted from sulphur dioxide and is linked to acid rain.
What is an alloy?
A metal mixed with a small amount of another metal to improve it's properties.
How can adding different sized metals together make a metal stronger?
The different sizes disturb the layered structure, so the layers can't slide over each other.
What does malleable mean?
You can change the shape
What two ways can the proportion of gold in an alloy be described as?
Carats or fineness
Give an example of a smart alloy.
Nitinol, an alloy of nickel and titanium.
What property does nitinol have?
If you bend it, it'll return to it's original shape when heated.