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Preparing For Chemistry 5070 P1 / P2

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So here's a revision thread , to prepare for the chemistry exam on Wednesday 30 May 2012 .

Let's start from Macromolecules (The last part of Organic Chemistry ) and move backwards . Post any important points you can think of . No questions please . For questions we have other threads ,this one is for revision .

Let's Begin With The Name Of Allah:

bismillah-irrahman-irrahim
 
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So here's a revision thread , to prepare for the chemistry exam on Wednesday 30 May 2012 .

Let's start from Macromolecules (The last part of Organic Chemistry ) and move backwards . Post any important points you can think of . No questions please . For questions we have other threads ,this one is for revision .

Let's Begin With The Name Of Allah:

bismillah-irrahman-irrahim

Nice idea :D :p

Macromolecules are large molecules built up from small units called monomers (which can be different or same) in a process called polymerisation .
There are two types of polymerisation
1.Condensation
2.Addition
Carry on from here :D
 
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In Addition polymerization a number of monomers join together to form a large higher molecular mass polymer .
Condensation polymerization , the same happens , but with the removal of molecules of water .

Now give the conditions :)
 
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In Addition polymerization a number of monomers join together to form a large higher molecular mass polymer .
Condensation polymerization , the same happens , but with the removal of molecules of water .

Now give the conditions :)
conditions ?? :confused:
 
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oh right, for condensation
we could see the amide or ester linkage.
i dont know about addition :unsure:
maybe the repeat unit ?

Only unsaturated monomers undergo addition polymerization as the double bond breaks and the join together . For condensation polymerization a molecule of water is discharged . So let's now discuss the examples .

Polyamides
Polyesters
 
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oh right, for condensation
we could see the amide or ester linkage.
i dont know about addition :unsure:
maybe the repeat unit ?

Yeah but the linkages wont help only to identify in addition u will always have a unsaturated monomer combining with a same monomer or a different one while in condensation u will always get a water molecule as the product and in our syllabus i guess we dont have unsaturated monomers for condensation polymerisation !

Now someone continue by saying abt disadvantage of plastics and two man made polymers!
 
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polyamide : nylon ( formed by dicarboxylic acid and diamine )
polyester : terylene ( formed by Dicarboxylic acid (with 2 –COOH groups) and diol (with 2 –OH groups) )

uses of nylon:
- a replacement of stockings and manufacture of garments to replace silk
- make tents and parachutes due to strength
- fishing lines
- rugs and carpets

uses of terylene:
- fabrics due to strength
 
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disadvantages of plastics:
- they are non-biodegradable – they cannot be decomposed by bacteria.
- they produce carbon dioxide when burnt – increases global warming.
 
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Only unsaturated monomers undergo addition polymerization as the double bond breaks and the join together . For condensation polymerization a molecule of water is discharged . So let's now discuss the examples .

Polyamides
Polyesters

Why u always write before me and exactly what i write :D :D :p :p :p !

Polyamides are polymers with amide linkage HN-CO and are found in nylon and a natural polymer protein .
In Nylon they are formed by combination of a monomer having -COOH linkages on both ends and a monomer with amine linkages on both ends -NH2 while protein is formed from monomers with amine linkages at one end and a -COOH group on one end !
 
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I guess we're done with Synthetic polymers right?
So now someone should tell us about Natural Polymers (Fats , Proteins , Carbohydrates) .
Remember , we only need to do the decomposition of Natural Polymers .
 
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Proteins sources are meat,fish, e.t.c and well its monomers are amino acids and the linkage is amide linkage...its decomposition ca nbe done throuygh hydrolysis enzymetic hydrolysis dilute acid sol + heat and dilute basic sol + heat....
STARCH are another natural polymers sources are grains and green vegetables its monomers are gulucose molecules and decompistion is same as proein....FATS are another type sources are vegetable oils and monomers are carboxylic acid and glycerol.......formation is 1 mole glycerol + 3 mol carboxylic acid=1 mole fat + 3 mole water.........i hope everyone knows about sponification :D
 
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On to Organic Chemistry!!

So i guess everyone already knows Nomenclature , which is the easiest part :p

So we'll start right with Alkanes !
 
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alkanes are saturated hydrocarbons in which there are single covalent bonds b/w carbon atoms...commonly called paraffin and they do two types of reaction 1=substitution and combustion....their general formula is CnH2n+2
 
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In the substitution reactions of Alkane, they undergo reactions with Group VII halogens, i.e fluorination, chlorination, bromination, iodination, and astatination reactions.
 
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