chem unit 4 polymers

three types of addition polymers

polyethene, polypropylene, polytetrafluorethene

LDPE

high pressure and temp, lots of branching thus less dispersion, low density, soft, low MP, amorphous

HDPE

low pressure and temp, minimal branching thus more dispersion, high density, hard, high MP, crystalline

three types of polypropene

atactic - random, syntactic - alternate, isotactic - same side thus strongest as enable packing

PTFE

strongest due to CF bonding

types of synthetic condensation polymers

polyesters - ester group in main chain, PLA - with bifunctional monomer, nylon - polyamide from adipic acid and hexanediamine

carbohydrate general formula

Cx(H2O)y

monosaccharide

one sugar unit with -OH group can be straight chain or ring form

examples of monosaccharides

glucose and fructose

ABBA

alpha below, beta above OH position related to chiral carbon

disaccharides

condensation reaction between hydroxyl group to create an ether/glycosidic bond between two monosaccharides

examples of disaccharides

sucrose (glucose+fructose), maltose and lactose

polysaccharide examples

starch and cellulose

natural condensation polymers

polysaccharides and polypeptides

proteins

made up of long chain amino acid

amino acid

made up of amino NH2 group (basic) and carboxylic COOH group (acidic) attached to alpha carbon

zwitterion

neutral dipolar ion in amino acid solution has NH3+ and COO-

peptide bond

link between two amino acids after condensation reaction

AABC

pH above pI anion, pH below pI cation

electrophoresis

electric field to seperate charged molecules

what makes a peptide pos charge

NH2 group and pH<pKa/pI, move towards neg electrode (cathode)

what makes peptide neg charge

COOH group and pH>pKa/pI, move towards pos electrode (anode)

amphiprotic meaning

can donate and accept H+

advantages of fermentation over hydration

cost effective cause less heat and pressure, lower enviro impact bc renewable sources

EP in conductometric titration

at min conductivity point

when does precipitate form

when Q>Ksp

how does buffer separate solution of 3 amino acids

when pH=pI stays in middle acts as zwitterion, when pH<pI go to neg cathode as becomes cation, when pH>pI go to pos anode as becomes anion

relationship between pH range and pKa value

when below range favours acid, and when above range favours ions

func group in aldose monosaccharide

-CHO