C10 Using our Resources Flashcards
What are the conditions of a Low Density poly(ethane) LPDE
Moderate temperature
High pressure
Catalyst
Flexible material- used for bottles and bags
What are the conditions for High Density poly(ethane) HDPE
Lower temperature
Lower pressure
Different catalyst
Rigid material- drainpipes, charger casing
What are the properties of thermosetting monomers?
Able to form cross links( covalent bonds) between chains
Polymer doesn’t melt when heated
These polymers are hard, strong a rigid- kettles
Properties of thermosoftening monomers?
Long individual chains tangled together
Weak intermolecular forces in between chains so can easily melt when heated and be remoulded
What is bioleaching and phytomining?
Bioleaching=Using bacteria to convert copper compounds into soluble copper compounds which can be extracted from the ore via displacement with scrap iron, or electrolysis from the leachate.
Phytomining=Growing a plant in copper rich soil, as the plant doesn’t use the copper it build up in the leaves. Harvesting, drying and burning the leaves creates a copper rich ash which can be displaced with scrap iron or use electrolysis to give a pure copper
Advantages and disadvantages of extraction from low grade ore techniques such as bioleaching and phytomining
Advantages: cheap, smaller environmental impact,less damage to habitats, less energy required, less climate change contribution
Dis- Phyotmining takes a long time
What are the three methods of protection from rusting?
Barrier
Sacrificial- when a more reactive metal is used to coat the iron
Other- combines barrier and sacrificial
—> galvanizing with zinc
Examples of barrier methods to protection iron rusting
Painting a metal or plastic coating
Electroplating-using electrolysis to coat iron with a different metal
Oiling/greasing-good for moving parts
What are the gas tests for:
Oxygen
Hydrogen
Carbon dioxide
Chlorine?
Oxygen-Glowing splint held in test tube-if splint relights oxygen is present
Hydrogen-Lighted splint held in test tube-if pop is head hydrogen is present
C02-Gas bubbled through limewater-if limewater turns cloudy white or milky C02 is present
Chlorine-Damp litmus paper held in test tube-if paper turns white chlorine is present
What are the ways of creating potable water from rain water, salty water and waste?
Rain water can be passed though filter beds and sterilised
Salty water can be desalinated-distilled or by reverse osmosis
Waste water can be cleaned be screening, sedimentation and aerobic digestion
What are composites made of?
A matrix/ binder -surrounds the reinforcement, minds it together
A reinforcement-fragments or Forbes within the matrix for extra strength
