Redox Rusting And Iron Flashcards
What is oxidation
Gain of oxygen
Loss of hydrogen
Loss of electrons
What is reduction
Loss of oxygen
Gain of hydrogen
Gain of electrons
What is redox reaction
When both oxidation and reduction happens
What is combustion and what happens during it
Is when something is burned, involves combining substance to be burned with oxygen
What is rusting
Rusting is when iron reacts with oxygen and water
What is rust a namr for
Hydrated iron(III) oxide
Fe2O3.xH2O
What speeds up rust
Salt
What are some problems with rust
Unsafe as it becomes weaker than the metal iron
Expensive as it can’t be recycled or reused so it has to be replaced
What are some ways of preventing rust
Oil or grease prevents water getting to iron(tools/bicycles)
Plastic costing used on clothing lined or handlebars of bicycles
Paint is another way of preventing it
What is galvanising
When coating of zinc is put on iron to prevent rusting
How do we extract aluminium
Using electrolysis
What are the three main materials used for extraction of iron
Coke
Limestone
Iron ore/haematite
What us the process if the blast furnace
1)coke is burned in hot air to form carbon dioxide which reacts with more coke to form carbon monoxide gas which is the reducing agent
C+O2=CO2
C+CO2=2CO
2) carbone monoxide reacts with iron three oxide because carbon more reactive. Takes oxygen away from iron. Iron is then in molten form and sinks to the bottom where it can be tapped off
Fe2O3+3CO=2Fe+3CO2
3) limestone added to remove any acidic impurities like silicon dioxide with high temp limestone thermally decomposes to form calcium oxide and carbon dioxide.
CaCO3=CaO+CO2
Calcium oxide then reacts with silicon dioxide to form calcium silicate(slag)
CaO+SiO2=CaSiO3
