C 3 Metals and their uses Flashcards
(15 cards)
What are the most common metals found in the Earth’s crust?
Aluminium, iron, copper
How are most metals found in nature?
As compounds (often oxides) in ores
What is an ore?
A rock that contains enough of a metal compound to make it economically worthwhile to extract
What method is used to extract metals less reactive than carbon?
Reduction with carbon (e.g. iron from iron oxide in a blast furnace)
Example: iron from iron oxide in a blast furnace
What method is used to extract metals more reactive than carbon?
Electrolysis of molten compounds (e.g. aluminium)
Example: aluminium
What are the disadvantages of using electrolysis to extract metals?
Very high energy cost
Expensive equipment
Why is recycling metals important?
Saves energy
Conserves natural resources
Reduces environmental damage from mining
What is an alloy?
A mixture of a metal with other elements, often to improve its properties
Why are alloys usually harder than pure metals?
Because the different-sized atoms distort the layers, making it harder for them to slide
What is steel?
An alloy of iron and carbon (may include other elements too)
Why is pure iron not useful for construction?
It’s too soft and malleable
Give one use each for:
a) Low carbon steel
b) High carbon steel
a) Car bodies
b) Cutting tools
What are the properties of copper that make it useful for wiring and plumbing?
Good conductor of electricity and heat
Can be bent (malleable)
Does not react with water
Why is aluminium used in aircraft?
It is low density and resists corrosion
Why is titanium used in surgical implants and aircraft?
It is strong, low density, and resistant to corrosion
