Polymers + Nylons - Unit 7

Question 1

How is an ester formed?

Answer 1

alcohol + carboxylic acid

alcohol + acid chloride

Question 2

Name the process and reaction and describe what is happening?

CH₃OH + CH₃COOH <–> CH₃COOCH₃ + H₂O

Answer 2

1 - Condenstraion reaction - water eliminated

2 - Esterfication - Ester link formed by condesnation reaction of OH group with COOh group

3 - Reaction conditions: conc. H₂SO₄

4 - Reverse reaction = Ester hydrolysis

Question 3

How to improve the yeild in this reaction:

CH3OH + CH3COOH <–> CH3COOCH3 + H2O

Answer 3

1 - Excess alcohol

2 - Water distilled off

3 - Sulfuric acid catalyst abrobrs some of the water formed

Question 4

Properties of Ester?

Answer 4

Have strong sweet smells

Question 5

Uses of Esters?

Answer 5

1 - Food flavourings

2 - Perfumes

3 - Solvents

Question 6

Polyermisation vs condenstaion?

Answer 6

1 - Polymerisation -monomer + monomer –> polymer

2 - Condenstaion monomer + monomer –> polymer + smaller molecule

Question 7

What two reactions forme polymers?

Answer 7

polymerisation and condenstaion

Question 8

What is a condensation polymer?

Answer 8

Polymer formed from condesnation reaction

Question 9

What two reactions form ester?

Answer 9

1 - Alchol + carboxylic acid

2 - Phenol + Acid anhydride - acud anhydirde as need more vigorus reacagnat as OH group in phenol less reacfive than OH group in alchohol

Question 10

How is an amide formed?

Answer 10

1- NH₂ group in amine reacts with COOh group in craboxylic acid in a condensation reaction

2 - Amide group - CONH formed

Question 11

What are nylons AKA?

Answer 11

ployamides

Question 12

Propeties of amines?

Answer 12

1 - Is a base

2 - because it can accept protons ad the lone pair of e - on the N can form a dative covalent bond with a H+ ion

3 - Small amines slightly fishy

4 - Large amines smell very fishy

Question 14

What are amides?

Answer 14

Carboxylic acid derivitives in which the OH group on the COOH is replaced with NH2

Question 15

How can polyamides/nylones be made?

Answer 15

1 - In a condensation reaction between a diamine and a carboxylic acid

2 - The polymaine contains amide (CONH) links between the monomers

Question 16

Why is a catalyst used alongs ide water to break down ana ester?

Answer 16

Ester and water recat very slowly

Question 17

Why is alkline hydrolysis preffered over acid?

Answer 17

1 - Goes to completion

2 - Non-reversable

Question 18

Common acid/alaki used for hydrolysis?

Answer 18

Alaki - NaOH

Acid - HCl

Question 19

How do amino aids vary?

Answer 19

Have vdifrent side chain

Question 20

What is the alpha crabon?

Answer 20

The first carbon atatched tot he COOH

Question 21

Properties amino acids?

Answer 21

form salts with acids

form salts with alakis

very soluble in water as basically ionic

Question 22

Suoer impossible vs non-superimipssoible?

Answer 22

super impoissible - when you rotate the imgaine it is not the same as the right hand image

Question 23

Enantomer?

Answer 23

non-siperimpossable mirror image molecules

Question 24

Proteins?

Answer 24

Condenstaion poluumers formed from amino acid monomers

Question 25

Use paper chromotogaohy?

Answer 25

Identify aminoa cids in protein Peptid ehydrolysed under reflux and product comapred to pure smaples amnio acids using paper chromotoggaphyn