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Name three uses for polythene?
Plastic bags, squeezy bottles, lunch boxes.
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List three reasons for use of polythene.
Strong, cheap and flexible.
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Name three examples of use of rigid pvc?
Pipes and gutters, window frames and curtain rails.
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List three reasons for use of rigid pvc.
strong, long lasting, weather resistant.
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Name three examples of use of flexible pvc?
insulation for electrical wires, hosepipes, shower curtains.
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List three reasons for use of flexible pvc.
strong, long lasting, electrical insulator.
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Name three examples of use of polystyrene?
food containers, yoghurt pots, electrical components.
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List three reasons for use of polystyrene.
Strong (but brittle), rigid, electrical insulator.
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Name three examples of use of expanded polystyrene (aeroboard)?
Packaging, house wall insulation, disposable coffee cups.
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List two reasons for use of expanded polystyrene (aeroboard)
extremely low density, good heat insulator.
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Name three examples of use of nylon?
Tights, ropes, and brushes.
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List three reasons for use of nylon.
Can be spun into fibres, hard-wearing, 'slippery'
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What are plastics?
Plastics are man made materials
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What are pastics made from?
Most are made from crude oil which is a thick black smelly liquid but for use crude oil must be refined.
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What is a catalyst?
A catalyst is a substance that speeds up chemical reactions but is not used up.
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What is Cracking?
Atfer fractional distillation of crude oil lots of large molecules are left.
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What is known as Catalytic Cracking?
Large molecules are broken down into smaller more useful molecules by heating them over a catalyst.
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What is polymessation?
NB: Making of plastic from crude oil involves 2 stages.
1. Production of monomess from curde oil during cracking.
2 The joining together of these monomess to make polymess.
Polymessation is the joining together of monomero to make polymess.
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Why is there so much plastic.? ( 7 reasons)
- 1. Cheap to make. 2 Easy moulded into shape.
- 3. Easy to maintain as it does not corrode.
- 4. Designed for different uses.
- 5. Insulator for heat and electricity.
- 6. Different colours. 7. Low density easy to work with.
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Name the properties of polythene.?
- High density - hard and rigid. eg . dustbin.
- Low density - soft and flexible eg. plastic bags.
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Name two categories of heating plastics?
Thermoplastics and thermosetting plastics.
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Explain thermoplastics.
Soften easily on heating . Can be easily remoulded.
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Explain thermosetting plastics.?
Do not soften on heating. They are hard and rigid.
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