Obtaining and using Metals Flashcards
What is an ore
.
A rock that contains enough metal to extract for a profit
Why are metals such as gold and platinum found as elements
They are very unreactive
How are metals that are less reactive than carbon extracted?
By heating them with carbon
How are metals that are more reactive than carbon extracted?
By electrolysis using a direct current.
Why are all metals not extracted by electrolysis?
It is more expensive
All metals are extracted from their ores by reduction. What is reduction?
The removal of oxygen
What is oxidation
The addition of oxygen
Corrosion or rusting is caused by a metal reacting with oxygen, what is another name for this process
Oxidation
Why should we recycle metals?
Natural reserves of metal ores will last longer
Less energy is needed to recycle metals than extract them from their ores.
It means less mining which causes noise and dust pollution.
Less pollution such as carbon dioxide and sulfur dioxide are produced which reduces global warming and acid rain respectively
Less waste in landfill sites
What are the properties of metals?
They are shiny, conduct heat and electricity.
They are malleable (can be hammered into shape)
They are ductile (can be stretched to make wires)
What properties of aluminium are useful
It has a low density(it’s light)
It does not corrode
What are the most useful properties of copper?
It’s a good electrical conductor.
It has a low reactivity.
What useful properties does gold have?
It is unreactive and does not corrode.
It is shiny and can be made into many different shapes.
It’s a great conductor of electricity
Why is iron mixed with carbon?
To make still which is stronger than iron
What is an alloy
A mixture of two metals
