C15: Using Our Resources Flashcards
What is corrosion?
The destruction of materials by chemical reactions with substances in the environment.
What is necessary for iron to rust?
Both air and water
How can corrosion be prevented?
Applying a coating that acts as a barrier, like greasing, paint or electroplating
What is bronze an alloy of? What is brass an alloy of?
Copper and tin. Copper and zinc
What are steels?
Alloys of iron that contain specific amounts of carbon and other metals
What are the properties of high carbon steel and low carbon steel?
High: strong but brittle. Low: softer and more easily shaped
What is the density of aluminium alloys?
Low
How is soda lime glass made?
Heating a mixture of sand, sodium carbonate and limestone
How is borosilicate glass made?
From sand and boron trioxide?
What type of glass melts at a higher temperature
Borosilicate glass
How are clay ceramics made?
Shaping wet clay and heating it
What is the difference between thermosoftening and thermosetting polymers?
Thermosoftening ones melt when heated but thermosetting ones don’t when heated
What are the conditions of the Haber Process?
450 degrees, 200 atm and an iron catalyst
What can ammonia be used to manufacture?
Ammonium salts and nitric acid
What 3 things are obtained by mining?
Phosphate rock, potassium chloride and potassium sulfate
What does the rusting of ion produce?
Hydrated iron (III) oxide
What are sacrificial methods?
Adding a more reactive metal on iron so that it doesn’t rust
What does brittle mean?
The object will snap easily
What are 2 main groups of ceramics?
Glass and clay ceramics
What are properties of glass?
Strong, good thermal insulators and transparent
What is a composite?
A material consisting of 2 or more materials with different properties that have been combined to produce a material with a more desirable property
What are the 2 components most composites are made from?
The reinforcement (long fibres or fragments) and the matrix (binds reinforcement and gets hard)
What 2 things does the property of a polymer depend on?
The monomer used and the conditions of the chemical reaction
What are properties of polymers?
Flexible, good insulators of heat and electricity and easily shaped
What conditions are needed for LDPE?
Moderate temperatures, high pressure and catalyst
What are uses of LDPE?
Carrier bags
What are uses for HDPE?
Drainpipes
How are the polymer chains in thermosoftening polymers held together?
By weak intermolecular forces
What types of reaction is the Haber Process?
Exothermic and reversible
How is the ammonia and the hydrogen/nitrogen separated?
Ammonia is condensed as it has a low boiling point, and the nitrogen and hydrogen are recycled
What is needed to favour the forward reaction in the Haber process?
Low temperature, high pressure due to moles
Why is ammonia important?
It is used in fertilisers
Where does the hydrogen for the Haber process come from?
Hydrocarbons
How does ammonia produce nitric acid?
It reacts with oxygen and water in a series of reactions
What is produced when phosphate rock reacts with nitric acid?
Phosphoric acid and calcium nitrate
What is produced when phosphate rock reacts with sulfuric acid?
Calcium sulfate and calcium phosphate
What is produced when phosphate rock reacts with phosphoric acid?
Calcium phosphate
