Polymers + Amino Acids

Question 1

What are condensation polymers?

Answer 1

• polymers that are formed through the polymerisation of monomers that eliminates molecules of water

Question 2

What are the three types of condensation polymers?

Answer 2

1. Polyesters
2. Polyamides
3. Polypeptides

Question 3

What are polyesters formed from?

Answer 3

• dicarboxylic acids and diols
• Teylene

Question 4

What are polyamides made from?

Answer 4

• dicarboxylic acids and diamines
• Kevlar, Nylon 6,6

Question 5

What are polypeptides made from?

Answer 5

• amino acids

Question 6

What is terylene made of?

Answer 6

• ethane-1,2-diol and benzene-1,4-dicarboxylic acid

Question 7

What are the uses of polyesters?

Answer 7

• plastic bottles, clothing, carpet

Question 8

What does an amide link look like

Answer 8

Question 9

What is nylon 6,6 made from?

Answer 9

1,6-diaminohexane and hexane-1,6-dicarboxylic acid

• used for clothing, carpet, ropes, parachutes

Question 10

What is Kevlar made from?

Answer 10

• benzene-1,4-diamine and benzene-1,4-dicarboxylic acid
• bulletproof vests, crash helmets, fire resistant material

Question 11

What is nylon 6 made from?

Answer 11

6-aminohexanoic acid

Question 12

Describe the trend of physical properties from addition polymers, polyesters and polyamides

Answer 12

• increases in rigidity
• increase in IMF between chains
• VDW -> d-d -> H bonding between chains

Question 13

Why are addition polymers inert?

Answer 13

• as they contain no polar bonds
• non-biodegradable

Question 14

Why are condensation polymers biodegradable?

Answer 14

• as they contain polar bonds and are thus able to be hydrolyses and readily attacked by nucleophiles

Question 15

What are the products if you hydrolyse a poly ester under basic conditions?

Answer 15

• salt of an acid
• alcohol

Question 16

What are the products if you hydrolyse a poly ester under acidic conditions?

Answer 16

• alcohol
• acid

Question 17

What are the products if you hydrolyse a polyamide under basic conditions?

Answer 17

• salt of an acid
• diamine

Question 18

What are the products if you hydrolyse a polyamide under acidic conditions?

Answer 18

• carboxylic acid
• diaminium ion

Question 19

Give disadvantages and advantages for using landfill to dispose of non-biodegradable polymers

Answer 19

• cheap
• requires lots of land

Question 20

Give disadvantages and advantages for using burning to dispose of non-biodegradable polymers

Answer 20

• produces heat energy
• releases CO2, CO and C
• some plastics release toxic styrene vapour

Question 21

Give disadvantages and advantages for using recycling to dispose of non-biodegradable polymers

Answer 21

• conserves oil reserves, saves energy from oil refining and reduces use of landfill
• exspensive (collection, transport and separation of plastics)

Question 22

What is a zwitterion

Answer 22

• an amino acid with a permanent positive and negative charge
• results in molecule being neutral overall
• ionic properties

Question 23

Describe the structure of an amino acid in acidic conditions

Answer 23

• high [H+]
• everything protonated

Question 24

Describe the structure of amino acids in an alkaline solution

Answer 24

• low [H+]
• everything deprotonated

Question 25

What is the structure of an amino acid at ph 7.00

Answer 25

Zwitterion

Question 26

What is the chemical definition of primary structure

Answer 26

- the linear sequence of AA in the protein chain joined together by peptide bonds

Question 27

What is the chemical definition of secondary structure of a protein

Answer 27

- The arrangement of the peptide-linked backbone of the amino acid chain - hydrogen bonds between polar C=O groups and N-H groups

Question 28

What are the four main interactions that contribute to the tertiary structure of a protein

Answer 28

Hydrogen bonds - between polar side chain groups Disulphide bridges (-S-S-) - between cysteine amino acids residues in the protein chain Salt bridges - ionic interaction between -NH3+ and -COO- side chain groups Hydrophobic and hydrophilic interactions

Question 29

How can you determine protein structure?

Answer 29

The primary structure of a protein can be determined by finding out the number of each type of amino acid present in the protein 1. Break protein down into original AA by boiling protein with conc HCl, amide bonds break 2. Separate AA with TLC

Question 30

What are the 2-deoxyribose units connected togehter by?

Answer 30

- phosphate ion - creating a sugar-phosphate backbone - bases are bound to the 2-deoxyribose and there are hydrogen bonds between bases that hold the two strands together

Question 31

On a 2-deoxyribose unit where does the phosphate and base bind?

Answer 31

- phosphate ion at carbon number 5 - eliminating water (OH from sugar and H from phosphate) - the phosphate ion then binds with carbon 3 on the next unit - base binds on carbon 1

Question 32

All bases contain the ……… group

Answer 32

NH2

Question 33

How many hydrogen bonds are there between C and G?

Answer 33

Three

Question 34

How many H bonds are there between A and T?

Answer 34

2

Question 35

What is cisplatin?

Answer 35

- Anticancer drug - square planar

Question 36

Describe the ligand substitution reaction cisplatin is involved in?

Answer 36

- nitrogen atoms on guanine molecules form dative covalent bonds with platinum is cisplatin, replacing the Cl- ions - it can also bind to other guanine residues on the same strand or between, dna cannot be replicated

Question 37

Why wont transplantin stop dna replication?

Answer 37

- would not bind to both chains

Question 38

What are the side effects of cisplatin

Answer 38

- binds to dna in healthy cells - healthy cells that replicate quickly (hair follicles) are significantly affected - indigestion/infertility