6. Metals Flashcards
Please send Lions, Camels, Monkeys And Colourful Zebras In Hollow Cages Securely Guarded
Potassium, Sodium, Lithium, Calcium, Magnesium, Aluminium, Carbon, Zinc, Iron, Hollow, Copper, Silver and Gold
What is a displacement reaction?
When a more reactive metal displaces a less reactive metal from its compound in aqueous solution
Displacement reactions
Produce metals and their compounds (aq)
Used to establish positions within the reactivity series
More reactive loses electrons (Oxidised)
Less reactive gains electrons (Reduced)
Another word for a displacement reaction?
REDOX reaction
Where does Carbon fit into the reactivity series?
Below Aluminium & above Zinc
Where does Hydrogen fit into the reactivity series?
Below Iron & above Copper
What do Gold, Silver & Platinum have in common?
They are all found in the Earth as a compound in an ore
What is an ore?
Ores are naturally occurring rocks that contain metal or metal compounds in sufficient amounts to make it economically worthwhile extracting them.
What kind of lattices do metals create?
Giant lattices
Copper
Used for wiring/plumbing, good conductor, can be bent but hard enough for pipes & doesn’t react with water
Iron
Iron from a blast furnace is only 96% iron
The impurities make it brittle & not very useful
Most is converted to Steel
Steel
Steel Iron and Carbon
High carbon Steels are hard
Low carbon steels are easily shaped
Stainless steel is corrosion resistant
What is an Alloy?
A mixture of two or more metals
Why are Alloys harder?
Their different sized atoms distort layers in structures, make it harder to slide
What is a shape memory alloy?
An alloy that returns to original shape when heat or electricity is passed through
ie Nitinol is used in dental braces
How are Metals less reactive then Carbon extracted?
They can be extracted from their oxides by reduction with Carbon i.e. Iron Oxide is reduced in a blast furnace to make Iron
Equations in a blast furnace
Carbon dioxide + Carbon –> Carbon Monoxide
Iron Oxide + Carbon Monoxide –> Iron + Carbon dioxide
How are metals more reactive than Carbon extracted?
From the electrolysis of molten compounds
Why are metals more reactive than Carbon expensive?
They have to be melted for electrolysis, this requires a lot of energy and this makes it very expensive
How is Copper extracted?
From Copper-rich ores by heating the ores in a furnace
Then purified via electrolysis
What is the problem with the extraction of Copper?
The supply of Copper-rich ores is being depleted
Traditional mining methods have serious environmental effects
Two new ways of Copper extraction from low grad ores
Phytomining
Bioleaching
What is phytomining?
Plants are placed in soil rich in metal compounds, the plants absorb the compounds through their roots, then the plants are burnt and the ashes contain the compounds
What is bioleaching?
Bioleaching uses bacteria to produce leachate solutions that contain metal compounds
How else can Copper be obtained?
Through the electrolysis of Copper salts using scrap iron
Why should we recycle metals?
Extracting them uses limited resources, and is expensive in terms of energy and in terms of effects on the environment
