Flashcards in Unit 2 Topic 7 Materials Deck (36):
Why nanoparticles have different properties to larger particles?
This is because they have a higher surface area to volume ratio
Give use for gold nanoparticles?
Catalysts to convert carbon monoxide in to carbon dioxide
Give 3 properties of silver nanoparticles?
Give 2 uses of carbon nano tubes?
- Mini electronic devices
- Smaller faster computers
How can nanoparticles be used as coating?
Thin layers of scratch resistant polymers can be used to protect lenses
Give 2 ways of extracting metals from ore?
What is electrolysis?
The breaking down of compounds in to simpler substances using electric current
What is an electrolyte?
An ionic compound that's been melted or dissolved
What is a cathode?
The electrode attached to the negative pole
What is an anode?
The electrode attached to the positive pole
What is an electrode?
Metal or Graphite rods placed in to liquid and connected to a supply of electricity
Which electrode are anions attracted to?
Which electrode are cations attracted to?
Give an observation of pure lead produced at the cathode after electrolysis?
Give a observation of pure bromine produced at anode?
Give an observation of pure lithium that forms at cathode?
Give an observation of pure chlorine produced at anode?
Pale green gas
How is Aluminium manufactured?
Electrolysis of Aluminium ore (Bauxite)
What is Bauxite?
Aluminium ore, which is Aluminium Oxide
What temperature is electrolysis of Aluminium carried out at?
Give 2 purposes of cryolite?
Lowers melting point of bauxite
Allows mixture of molten liquids to conduct electricity
Give 2 reasons to recycle aluminium?
Most cost effective metal to recycle
Recycling aluminium requires only 5% of energy required to manufacture aluminium
How is Iron extracted from its ore?
Blast Furnace (Chemical Reduction)
What is Iron ore also known as?
Give the 3 stages of the extraction of Iron from its ore?
- 1. Formation of reducing agent ( Carbon Monoxide)
- 2. Reduction of iron oxide to iron
- 3. Removal of impurity
Give equations of all the reactions in extraction of iron?
- C + O2 ---> CO2
- CO2 + C ---> CO
- Fe2O3 + 3CO ---> 2 Fe + 3CO2
- CaCO3 ---> CaO + CO2
- CaO + SiO2 ---> CaSiO3
What 3 reactants are used in extraction of iron?
Iron ore ( Haematite)
Coke ( Carbon)
Why is Limestone used in extraction of iron?
It thermally decomposes to Calcium Oxide, which then reacts with the sand impurity in iron ore, Silicon Dioxide. This forms Calcium Silicate, which is also known as slag, which then floats on top of the pure iron as it is less dense
What is Calcium silicate also known as?
Give 2 uses of slag?
Build foundations for buildings
Give 2 ways in which production of iron helps the economy?
Give 3 environmental problems with production of iron?
Unsightly slag heaps
Give 1 disadvantage and 2 advantages of recycling the raw materials used in iron production?
- Sorting recycled materials is expensive
- Less energy used
- Saves resources
Give 2 disadvantages and 1 advantage of disposing or incinerating materials?
- Toxic / polluting products released in to atmosphere
- Landfill wastes land
- Heat energy from incineration can be harnessed to generate electricity
Give 2 disadvantages and 1 advantage of producing new materials?
- More mining and drilling for materials
- More pollution
- More jobs created