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- 1c1-why do we use additives ?To add flavour
bring out the taste
preserve food
act as an emulsifier - 2c1-What are the uses of strong polymers?strong/ridged polymer have high density polythene so they are used to make plastic milk bottles
- 3c1-What are the uses of light/stretchable polymers?They have low density polythene so are used for plastic bags and squeeze bottles( low density polythene has a low melting point so it wont be good for anything that will get hot).
- 4c1-Is PVC strong or weak?It is strong and durable as well as being able to change between ridged(for window frames) or stretchy(for synthetic leather)
- 5c1-What do we uses polystyrene foam for and why?We use it for packaging to protect breakable things and disposable coffee cups. This is because the trapped air in the foam acts as a brilliant thermal insulator.
- 6c1-Name a type of synthetic polymer?Nylon
- 7c1-what do we use nylon for?We often use it to make clothes, however they aren't very strong on their own, but can be coated with polyurethane. This then makes the material tough, hard-wearing, waterproof, and reflects the UV light.
- 8c1- What do we use hydrocarbons for?powering vehicels
heating homes
Making roads - 9c1- What 2 types of bonds are their in crude oil?Strong covalent bonds - within each hydrocarbon molecules
Intermolecular forces of attraction - between different hydrocarbon molecular in the mixture. - 10c1-What is the problem with coating polyurethane?It doesn't let water vapor pass through, so if you start to sweat it will condense inside the coat and become uncomfortable( isn't breathable)
- 11c1-How do you create GORE-TEX ?By laminating a thin film of plastic (expanded PTFE) onto a layer of another fabric e.g nylon or polyester. (makes it sturdier).
- 12c1-PTFE propertiesHas tiny holes which a lows water vapour to pass through
Breathable
waterproof(the holes are too small to let rain droplets pass through)
repels liquid water
great for outdoorsy types. - 13c1- Why are non-biodegradable plastics hard to dispose of ?Because, they don't rot which means they can not be broken down by micro-organisms. They take many years to decompose so will fill landfills up very quickly(waste of land). And when we burn them they release acidic gases(sulfur dioxide, hydrogen chloride, hydrogen cyanide.
- 14c1- What should we do with our plastics?it is best to reuse plastics many times as possible and then recycle them, however it is difficult and expensive.
- 15c1-What is a hydrocarbon ?Any compound only formed by carbon and hydrogen atoms (alkane) But an ester isn't due to having oxygen atoms in it.
- 16c1- Are hydrocarbons useful in chemicals and why?Yes, because they are used in fuels like petrol and deisel and also in plastics.
- 17c1- Are alkanes single or double bonded?single covalent bonded ( c-c )
- 18c1- are alkanes saturated or unsaturated?saturated
- 19c1- How do you tell the difference between an alkane and an alkene?By adding it to bromine water(bright orange). If it is decolourised it is an alkene
- 20c1- Why wont alkanes form polymers?Because they have no double bonded to open up
- 21c1- What are the first 4 alkanes ?methane, ethane, propane, butane
- 22c1- What is the formula for any alkane ?CnH2n+2
- 23c1- Are alkenes double or single bonded ?They are double bonded ( c=c )
Thery contain at least one covalent bond. - 24c1- Are alkenes saturated or unsaturated?They are saturated . They can form polymers by opening up their double bonds and join onto other bonds to hold hands in a long chain.
- 25c1- Are alkenes more reactive than alkanes?Yes , because they can form polymers by opening up their double bonds
- 26c1- What are the first three alkenes ?ethene,
propene
butene - 27c1- How is crude oil formed ?buried remains of plants and animals, ( a type of fossil fuel)
- 28c1- What conditions are needed to make crude oil?high temp
high preassure - 29c1-What is crude oil a mixture of ?lots of different hydrocarbons, however the the chains can be different lengths
- 30c1- How is crude oil separated ?By fractional distilation
- 31c1- What happens to the oil ?It is heated until it has turned into a gas. The gases enter into a fractionating column. (The liquid bitumen is drained off at the bottom).
- 32c1- Is the top hotter than the bottom?no, the bottom and top are both extremely hot, but it is slightly cooler at the top.
- 33c1- What chains enter the bottom of the column?The longer hydrocarbon chains exit lower down due to having a higher melting point. It then turns into a liquid and drains out.
- 34c1- What chains enter at the top of the column?Shorter hydrocarbons have a lower boiling point to they drain out later on near the top where it is cooler.
- 35c1- What does each fraction contain?a mixture of hydrocarbons with similar boiling points. They are separated into different fractions.
- 36c1- What happens when you increase the sizes of a hydrocarbon.The boiling point increases
Becomes less flammable
Doesn't flow as easily (viscous)
Less volatile - 37c1- What happens when the crude oil mixture is heated?It is given extra energy which makes it move about more. Eventually the molecule will overcome the intermolecuelar forces.
- 38c1- What is the strongest at holding the molecules together: covalent intermolecular forcescovalent because they don't break. That is why
- 39c2-
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- GCSE Chemistry FlashCards sobre Sem título, criado por ellie.whatrup em 31-03-2016.
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