Flashcards in Topic 4 - Obtaining And Using Metals Deck (20)
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1
Metals that react to form compounds are found naturally in
The earths crust
2
If a compound contains enough of the metal to make it worthwhile extracting it's called
A metal ore
3
Metal ores are a
Finite resource - limited amount
4
The more reactive a metal is
The harder it is to extract from a compound
5
Metals react with oxygen to form oxides. What is this process called?
Oxidation
6
A reaction that separates a metal from its oxide is called a
Reduction reaction
7
Methods of extraction are linked to
The order of reactivity
8
Only metals that are less reactive than carbon can be extracted by
Reduction reaction with carbon - this is done by heating the ore with carbon
9
Very reactive metals form
Very stable ores
10
Elements that are more reactive than carbon have to be extracted using
Electrolysis
11
Electrolysis uses electricity to
Separate the metal from the other elements in the compound
12
What are typical properties of metals
- strong but can be bent
- conductors of heat
- conduct electricity well
13
What are the properties of aluminium
- low density
- corrosion resistant
- pure aluminium isn't particularly strong but can form hard alloys
- useful structural material
- can be used for window frames, electricity cables, aircraft
14
What are the properties of copper?
- hard/strong
- high melting point
- good conductor of electricity
- useful for electrical wires or pipes
15
What are the properties of gold?
-shiny
- easy to shape
- used for jewellery or anything where you need a metal that won't react with anything e.g tooth fillings Or in electrical circuits
16
Corrosion in metals occurs because of
Metals being oxidised
17
Allots are harder than pure metals because
- different elements have different sized atoms
- if a different element is added to a metal, the smaller atoms will upset the layers of pure metal atoms and make it more difficult for them to slide over each other
18
Smart alloys have a
Shape memory ( they return to their original shape)
19
An example of a smart alloy is
Nitinol (alloy of nickel and titanium)
20