Transcript Chemistry_

Kevlar
KevlarTM is a synthetic polymer, the structure is shown below:
n is a very large number
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Exercise: New Materials
1. Who invented KevlarTM?
It was invented by Stephanie Kwolek (1965)
2. KevlarTM is a synthetic polymer. What does the word synthetic
mean? Can you name another synthetic substance?
Synthetic means artificial (man-made), TeflonTM is an
example of another synthetic substance
3. Can you list three properties of KevlarTM that make it so useful?
Properties include fire resistance, high tensile strength,
lightweight(ness) and flexibility
4. Describe some of the uses of KevlarTM.
Bullet-proof vests, sports equipment, aircraft manufacture and
fibre optics
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IT: Teflon
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Exercise: Testing For Alkenes
Describe the test, using bromine water, that allows you
to distinguish between an alkane and an alkene.
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Alcohols
Methanol belongs to a group of compounds called the
alcohols. The alcohols have a similar structure to the alkanes
but with a –OH group replacing one of the hydrogens.
Methane - CH4
Methanol - CH3OH
It is this –OH group that is responsible for the characteristic
properties of the alcohols.
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Ethanol From Bio-waste
E-coli bacteria, using genetic modification techniques, can
have ‘ethanol’ genes inserted. This gives the E-coli the
ability to produce ethanol from bio-waste sugars.
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Naming Esters - Spot The Pattern!
Methyl methanoate - HCOOCH3
Ethyl methanoate - HCOOC2H5
Propyl methanoate - HCOOC3H7
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IT: Properties
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Carboxylic Acids - Reactions
Carboxylic acids are neutralised by alkalis.
Looking at the neutralisation reaction of ethanoic acid and sodium
hydroxide the word equation is:
Ethanoic acid + sodium hydroxide  sodium ethanoate + water
This is just the acid and alkali reaction you will have seen before
but with a carboxylic acid:
ACID + ALKALI  SALT + WATER
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IT: Carboxylic Acids
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Unsaturated Fatty Acids - Oleic Acid
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Saturated Fatty Acids - Stearic Acid
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Glycerol
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