Metals and their extraction (NEW) Flashcards
What is the source of most metals?
Ores (minerals found in the Earth’s crust). They contain metal compounds, from which metals can be extracted
What happens when you put a more reactive metal into a less reactive metal in a compound
It replaces it (called a displacement reaction)
What is oxidation?
The gain of oxygen/ the loss of electrons
What is reduction?
The loss of oxygen / the gain of electrons
- happens at CATHODE
When an element is more reactive than carbon it is displaced using?
Electrolysis
What is Iron ore used for in a blast furnace?
Source of iron
What is Coke used for in a blast furnace?
as a fuel and to produce carbon monoxide for the reduction
What is Limestone used for in a blast furnace?
to remove impurities
What is hot air used in blast furnace?
provides oxygen so that coke can burn
What is electrolysis?
The process by which ionic substances are decomposed into simpler substances when an electric current is passed through them
What is the equation at the CATHODE for the extraction of Aluminium Oxide? (Al 3+)
Al3+ + 3e- → Al
What is the equation at the ANODE for the extraction of Aluminium Oxide?
2O2- → O2 + 4e-
How can you save energy during electrolysis of Aluminium
ALUMINIUM OXIDE dissolves in molten cryolite at a temperature much lower than its melting point, therefore saving energy.
What are the properties of Iron
Strong and hard
What are the properties of Aluminium
- Strong
- low density
- good conductor of heat
- electricity
- resistant to corrosion.
What are the properties of Titanium?
- Hard
- strong
- low density (airplane bodies)
- resistant to corrosion
- high melting point.
What are the properties of Copper?
- Very good conductor of heat and electricity
- malleable
- ductile (wiring)
- non toxic (saucepans)
What are the general properties of TRANSITION METALS?
- found in the centre of the Periodic Table
- high melting and boiling points
- malleability
- high density
- good electrical
- thermal conductivity
What is special about transition metals?
They can form more than one type of ion,
What is the equation at the CATHODE during electrolysis of water?
4H+ + 4e– → 2H2
What is the equation at the ANODE during electrolysis of water?
4OH– → 2H2O + O2 + 4e–
Why do we electroplate metals
Decoration and protection
When COPPER (CU) is present and reacts with HYDROXIDE (OH) what colour does it make?
blue precipitate
If IRON (FE3+) is present and reacts with HYDROXIDE (OH) what colour does it make?
Brown precipitate
IF IRON (FE2+) is present and reacts with HYDROXIDE (OH) what colour does it make?
green precipitate
What is a alloy?
a mixture made by mixing molten metals
How can an alloys properties be modified?
By changing its composition.
How is copper purified by electrolysis?
The ANODE is made from IMPURE copper and the CATHODE is made from PURE copper.
What are some factors which impact locations of siting of plants for extraction?
- close proximity to a power station
- near the coast to allow for the import of raw materials
- near roads and railway lines to allow for the product to be taken to where it is needed
- near a town or city, so that workers have somewhere to live close by
What is the reaction for CARBON MONOXIDE in a blast furnace?
Oxygen from the hot air reacts with carbon (coke) to form carbon monoxide.
This is an exothermic reaction and heats the furnace.
2C + O2 → 2CO
What is the reaction for IRON in the blast furnace?
Carbon monoxide then reacts with iron(III) oxide to give iron and carbon dioxide
Fe2O3 + 3CO → 2Fe + 3CO2
What is the reaction for CALCIUM OXIDE in a BLAST FURNACE?
Limestone decomposes thermally to form calcium oxide + Carbon Dioxide
CaCO3 → CaO + CO2
What is the reaction for SLAG in a BLAST FURNACE?
Calcium reacts with silicon dioxide (sand) to form slag.
CaO + SiO2 → CaSiO3
What things are formed in a blast furnace?
- Carbon Monoxide
- Iron
- Calcium Oxide
- Slag
When in ionic solutions , when is hydrogen formed at the CATHODE?
If the metal is more reactive than hydrogen
What is less reactive than hydrogen?
- copper
- silver
- gold
