Polymers And Life

Question 1

Give the products of the following reactions:
• Acid + Base/Alkali
• Acid + Metal
• Acid + Carbonate

Answer 1

• Salt + Water
• Salt + Hydrogen
• Salt + Water + Carbon Dioxide

Question 2

Give the structure of Ethanoyl Chloride

Answer 2

CH3COCl (Must have C=O and C-Cl)

Question 3

What conditions and reagents are required for esterification?

Answer 3

• Alcohol and Carboxylic Acid OR Alcohol and Acid Anhydride OR Alcohol and Acyl Chloride OR
Phenol and Acid Anhydride OR
Phenol and Acyl Chloride
• Few drops of conc. acid catalyst
• Boil under reflux

Question 4

What defines whether an amine is Primary, Secondary, or Tertiary?

Answer 4

The number of Carbons the Nitrogen is bonded to

Question 5

Give the structure of an amide bond AND state how it can form

Answer 5

• RCONHR’ (C=O, C-N, N-H)
• Can occur via a condensation reaction with a Carboxylic Acid, Acid Anhydride, Acyl Chloride

Question 6

Give two properties of amines that affect how they react

Answer 6

• Base
• Nucleophile
• Ligand

Question 7

Draw the repeat unit of Nylon 6,10

Answer 7

-(-NH(CH2)6NHCO(CH2)8CO-)-n
(Amide bonds drawn correctly)

Question 8

At room temperature, amino acids are crystalline solids with high MP. Explain why

Answer 8

• This is because amino acids exist as zwitterions, so form very strong ionic bonds between molecules
• Meaning a lot of energy is required to break these bonds

Question 9

Give the reagents and conditions for hydrolysis reactions (of proteins/esters/amides) in the lab

Answer 9

• MODERATELY conc. AQUEOUS acid/alkali solution (Ideally HCl or NaOH)
• Boil under reflux

Question 10

Give the differences between a chromatography experiment for amino acids and one for aspirin

Answer 10

• Aspirin can work with either paper chromatography or TLC, whereas amino acids primarily use paper chromatography
• Ninhydrin solution is used instead of Iodine/UV to locate the amino acids spots. It turns purple in the presence of amino acids

Question 11

State and explain the requirement for a molecule to exhibit enantiomerism

Answer 11

• Must contain a chiral/asymmetric carbon that is bonded to 4 different groups/atoms
• So forms two possible molecules that are mirror images of one another and are non-superimposable onto each other

Question 12

Define the tertiary structure of a protein

Answer 12

It is the OVERALL 3D SHAPE that arises due to IDID, hydrogen, ionic, and disulfide (covalent) bonding caused by the folding of the tertiary structure

Question 13

Describe the secondary structure of a protein

Answer 13

Section of the protein chain folded into an alpha helix or beta pleated sheet due to hydrogen bonds between amino acids

Question 14

What is the pharmacophore of a molecule?

Answer 14

The PART OF THE MOLECULE that is responsible for it’s medicinal/biological properties

Question 15

Describe how an enzyme works

Answer 15

• Active site of enzyme is determined by specific tertiary structure and is complementary to a specific substrate
• Substrate fits into/binds with active site
• Bonds within the substrate weaken
• Substrate reacts/breaks apart
• Products leave the active site

Question 16

Describe how a competitive inhibitor works

Answer 16

• Inhibitor has a similar shape to substrate/is complementary to the shape of the active site
• It blocks the active site, taking up space and preventing substrate from binding
• So no active sites are available for reaction, so no reaction

Question 17

Give 5 ways that an enzyme can bond to a substrate molecule

Answer 17

• Hydrogen bonding
• Ionic bonding
• Ion-dipole bonding
• Dative covalent bonding
• IDID bonding

Question 18

Describe the structure of DNA

Answer 18

• DNA is a condensation polymer formed from nucleotide monomers. • Each nucleotide consists of a sugar, a phosphate, and a base
• Two strands of DNA arranged antiparralel with hydrogen bonds between complementary base pairs to create one DNA molecule

Question 19

Which functional group on a molecule of tRNA carries the amino acid? What bond does it form with the amino acid?

Answer 19

• OH/Alcohol group
• Forms an ester bond

Question 20

What reagent can be used to turn propan-2-ol into 2-aminopropane?

Answer 20

NH3/Ammonia

Question 21

If a reactant is second order, then ___ molecules of this reactant must react in the RDS

Answer 21

Two