Sources Of Metals, Extracting metals, Using Metals And Alloys Flashcards
What is a metal ore?
A metal ore is a rock that contains enough of the metal to make it worthwhile extracting.
What are some examples of ways we can extract metals from their ores?
Some examples are through processes such as electrolysis, using a blast furnace or by reacting with more reactive material.
In many cases, the ore is an…
In many cases the ore is an oxide of the metal.
The extraction of these metals from their ores is usually what type of process and why?
The extraction of these metals is a reduction process since oxygen is being removed (when the ore is an oxide of the metal).
What is the name for an iron ore?
haematite
What is the name for an aluminium ore?
bauxite
Do unreactive metals have to be extracted chemically and explain why?
Unreactive metals do not have to be extracted chemically as they are often found as the uncombined element. This occurs as they do not easily react with other substances due to their chemical stability
What are some examples of unreactive metals?
Examples include gold and platinum which can both be mined directly from the Earth’s crust.
Where are the most reactive metals (on the reactivity series)?
The most reactive metals are at the top of the series.
What determines how reactive a metal is and it’s position on the reactivity series?
The tendency to become oxidised is linked to how reactive a metal is and therefore its position on the reactivity series
Metals higher up are therefore less resistant to oxidation than the metals placed lower down which are more resistant to oxidation
How can we determine a metal’s method of extraction and explain?
The position of the metal on the reactivity series determines the method of extraction
Higher placed metals (above carbon) have to be extracted using electrolysis as they are too reactive and cannot be reduced by carbon
Lower placed metals can be extracted by heating with carbon which reduces them
Why can’t we extract higher-placed metals (above carbon) by carbon?
Higher placed metals (above carbon) are too reactive and therefore cannot be reduced by carbon
What happens to lower-placed metals when we extract them?
Lower placed metals can be extracted by heating with carbon which thus reduces them
Which metals are extracted by electrolysis of the molten chloride or molten oxide?
Potassium
Sodium
Lithium
Calcium
Magnesium
Aluminium
Briefly describe electrolysis
Large amounts of the electricity is required and it is an expensive process.
How are Potassium, Sodium, Lithium, Calcium, Magnesium and Aluminium extracted from their ores?
Extracted by electrolysis of the molten chloride or molten oxide
Which metals are extracted by heating with a reducing agent such as carbon or carbon monoxide in a blast furnace?
Zinc
Iron
Hydrogen
Copper
Briefly describe extraction by heating with a reducing agent (like carbon or carbon monoxide) in a blast furnace.
Cheap process as carbon is cheap and can be source of heat as well
How are Zinc, Iron and Copper extracted from their ores?
Extracted by heating with a reducing agent such as carbon or carbon monoxide in a blastfurnance
How are silver and gold extracted from their ores?
They are not extracted from ores, as they are unreactive and found as pure elements.
Uses of Aluminium
Aeroplane bodies
Overhead power cables
Saucepans
Food cans
Window frames
Property of aluminium in aeroplane bodies
High strength-to-weight ratio (low density)
Property of aluminium in overhead power cables
Good conductor ofelectricity
Property of aluminium in saucepans
Good conductor of heat
Property of aluminium in food cans
Non-toxic, resistant to corrosion and acidic food stuffs, malleable
Property of aluminium in window frames
Resistant to corrosion
Uses of copper
Electrical wires and water pipes
Property of copper in electrical wires
Good conductor of electricity and malleable
Property of copper in water pipes
Easy to work with and bend, non- toxic and unreactive (does not react with water)
What are the types of steel?
Mild steel, high carbon steel, low alloy steel and stainless steel
Describe mild steel (iron alloyed with…, the use and most important property)
Iron alloyed with 0.25% carbon
Use = Car body panels, wires
Most important property = Soft and malleable
Describe high carbon steel (iron alloyed with…, the use and most important property)
Iron alloyed with 0.5-1.4% carbon
Use = Tools and chisels
Most important property = Hard
Describe low alloy steel (iron alloyed with…, the use and most important property)
Iron alloyed with = 1-5% of other Metals (Chromium, Nickel, Titanium)
Use = Construction, bridges, high speed tools
Most important property = Hard and strong, low ductility and malleability
Describe stainless steel (iron alloyed with…, the use and most important property)
Iron alloyed with = 20% Chromium and 10% Nickel
Use = Cutlery and sinks, chemical plants
Most important property = Strong and resistant to corrosion
What are alloys?
Alloys are mixtures of metals, where the metals are mixed together physically but are not chemically combined
They can also be made from metals mixed with nonmetals such as carbon
Describe the properties of alloys in comparison to the metals they contain and explain why
Alloys often have properties that can be very different to the metals they contain, for example they can have greater strength, hardness or resistance to corrosion or extreme temperatures. This is due to the fact that alloys contain atoms of different sizes, which distorts the regular arrangements of atoms
This makes it more difficult for the layers to slide over each other, so they are usually much harder than the pure metal.
Why are alloys usually much harder than the pure metal?
Alloys contain atoms of different sizes, which distorts the regular arrangements of atoms
This makes it more difficult for the layers to slide over each other, so they are usually much harder than the pure metal
