Extraction reactions of metals Flashcards
List the methods of extracting a metal from its oxide (3)
Displacement reaction with Carbon, Electrolysis, Displacement reaction with another more reactive metal
What will happen in a reaction between Zinc Sulphate + copper
No reaction
What will happen in a reaction between Copper Sulfate + Zinc
Copper Sulfate + Zinc to Zinc Sulfate + Copper
What is the symbolic equation between Copper Sulfate and Zinc
CuSO4+Zn → ZnSO4+ Cu
What is the Termite Reaction+ equation
It is displacement, exothermic reaction between Fe2O3+2Al → 2Fe+Al2O3
What is being used to extract iron from its ore?
Blast furnace
What chemicals are used for iron extraction?
Iron ore is mixed with Coke and Limestone
Why is Limestone being used in the extraction(equation + state symbols)
To remove impurities from iron ore. Limestone is decomposed in heat. CaCO3(s) → CaO(s)+CO2(g). Calcium oxide reacts with silicon dioxide which is a main impurity. CaO(s)+SiO2(s) → CaSiO3(l)
What is slag? What happens to it?
Calcium silicate (CaSiO3) It float on top of the molten iron and gets removed
Why is Coke burned with oxygen? (equation + state symbols)
In order to react with oxygen and form CO2. C(s)+O2(g) → CO2(g)
What happens to carbon dioxide? (Iron extraction stage 2) (equation + state symbols)
At high temperatures carbon dioxide is reduced to carbon monoxide CO2(g)+C(s) → 2CO(g)
What happens to carbon monoxide? (Iron extraction part 3) (equation + state symbols)
Carbon monoxide reduces the iron in the haematite. Fe2O3(s)+3CO(g) → 2Fe(l) + 3CO2(g)
What is haematite?
Iron oxide Fe2O3
What happens to iron as the % of carbon increases? (3)
Cost decreases
Becomes more brittle
It becomes softer
When does Iron rust? How can this process be increased?
In presence of water and oxygen. Add salt
How to prevent rusting(5)
Paint Coating Oil or grease Covered with plastic Alloying Galvanising
What is Alloying of iron
Adding Chromium and Nickel to make stainless steel
What does alloying do?
Provides a strong oxide layer that protects the iron
What is Galvanising?
Coating with a layer of zinc
Why does Galvanising help?
Zinc is more reactive than iron, so corrodes instead of iron.
What is being used to extract aluminium?
Electrolysis
What is the overall reaction for extraction of aluminium?
2Al2O3 → 4Al+3O2
Aluminium oxide has a very high melting point. What is done to it to reduce it?
Molten cryolite is added
What happens to aluminium ions during electrolysis?(electroe equation)
They get attached to cathode and reduced by gaining electrons
AL3+ + 3e- → Al
What happens to carbon anodes?
They react with oxygen at high temperatures to produce carbon dioxide and have to be replaced every several days
Is pure aluminium strong?
No
What are the advantages of Aluminium (7)
Aluminium oxide is strong It has low density Conducts electricity Resists corrosion Has a shiny appearance Good strength Conducts heat
What is decomposition?
Breaking down of substance into simpler substances
