Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry > PR- Polymer Revolution > Flashcards

PR- Polymer Revolution Flashcards

1
Q

What conditions are required for electrophilic addition of alkenes using Br2?

A

Room temperature and pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What conditions are required for electrophilic addition of alkenes using Br2 (aq)

A

Room temperature and pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the difference between the products of electrophilic addition using Br2 and Br2 (aq)?

A

Br2 simply adds two bromines across the double bond. Br2(aq) is in a solution with water molecules so the carbocation can be attacked by water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What conditions are required for electrophilic addition of alkenes using HBr (aq)

A

Aq solution, room temperature and pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What conditions are required for electrophilic addition of alkenes using water (H2O)?

A

Phosphoric acid/ silica; 300 degrees C and 60 atm

OR

Conc. sulfuric acid, then water at 1 atm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What conditions are required for electrophilic addition of alkenes using hydrogen/H2?

A

Platinum catalyst, room temperature + pressure

OR
Nickel catalyst at 150 degrees C and 5 atm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the conditions required for electrophilic addition using platinum as a catalyst?

A

Room temperature and pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What conditions are required for electrophilic addition of alkenes using nickel as a catalyst?

A

150 degrees Celsius, 5 atm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What conditions are required for electrophilic addition of alkenes using phosphoric acid as a catalyst?

A

300 degrees Celsius; 60 atm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What conditions are required for electrophilic addition of alkenes using silica as a catalyst?

A

300 degrees Celsius; 60 atm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What conditions are required for electrophilic addition of alkenes using concentrated sulphuric acid as a catalyst?

A

That catalyst followed by water at 1 atm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is electrophilic addition?

A

The addition of an electrophile across a double bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is an electrophile?

A

A partially positively charged particle that is attracted to an electron rich region (C=C bond)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does an electrophile react?

A

Accepts a lone pair of electrons to form a covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a carbocation?

A

A hydrocarbon with a positive charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does hydration of alkenes form?

A

Alcohols

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How is ethanol formed by ‘steam hydration’?

A

Phosphoric acid/ silica; 300 degrees C and 60 atm

Water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the test of unsaturation?

A

Bromine water

Brown —> colourless

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What reaction does gaseous HBr involve in electrophilic addition?

A

Radical addition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Why does the bromine water turn colourless?

A

A dibromoalkane is formed

21
Q

What reagents are needed to make alcohols from alkenes?

A

Conc. sulfuric acid, then water at 1 atm

22
Q

How are hydrogenated fats produced?

A

Hydrogen; platinum catalyst, room temperature + pressure

23
Q

What is the desired quality of hydrogenated fats?

A

Hardening; to be solid at room temperature

24
Q

What is a polymer?

A

A long molecule made up from lots of small molecules called monomers

25
Q

What are copolymers?

A

When two different types of monomers are joined in the same polymer chain.

26
Q

What is the process that turns alkenes into polymers?

A

Addition polymerisation

27
Q

What is an elastomer?

A

Soft and springy polymers that can be deformed and go back to their original shape.

28
Q

Give an example of a plastic

A

poly (ethene)

29
Q

Is poly (propene) a plastic or fibre?

30
Q

Why can Nylon be used as a fibre?

A

Does not deform easily; Can be made into strong, weavable threads.

31
Q

How is FLEXIBILITY of a polymer obtained?

A

The chains need to be able to slide past each other

The stronger the intermolecular forces, the less flexible the polymer.

32
Q

How does BRANCHING affect a polymer?

A

Straight chains can pack more closely together

33
Q

How does STEREOREGULARITY affect a polymer?

A

Regular side group orientation means the chains can pack tightly together

34
Q

How does CHAIN FLEXIBILTY affect a polymer?

A

Hydrocarbon chains are VERY flexible and can take up many orientations

35
Q

How does CROSS LINKING affect a polymer?

A

Covalent bonds can make the polymer harder and more difficult to melt.

36
Q

What two groups describe the way polymers behave when HEATED?

A

Thermoplastics and Thermosets

37
Q

What is the difference in the structure of thermoplastics and thermosets?

A

Cross-linking

38
Q

What is bakelite?

A

Phenol and methanal

39
Q

What happens when bakelite is heated?

A

It chars and decomposes

40
Q

Is bakelite soluble in water?

41
Q

What is the appearance of bakelite?

A

It’s brown and used in electrical insulators

42
Q

What is the effect of chain length on the solubility of alcohols?

A

As chain length increases, solubility decreases

After butane everything is insoluble

43
Q

Why are all alkanes after butane insoluble?

A

Hydrogen bonding can’t overcome the strength of the ID-ID all across the molecule

44
Q

What are polyhydric alcohols?

A

Alcohols with more than one OH group

45
Q

What is an alkoxy group?

46
Q

How can aldehydes/ketones be reduced back into alcohols?

A

Sodium tetrahybridoborate

NaBH4

47
Q

How do you increase the chain length of aldehydes/ketones/polymers?

A

Cyanide via nucleophilic addition

48
Q

How can you distinguish between aldehydes and ketones?

A

Fehling’s solution
Aldehydes are oxidised to carboxylic acids
The solution goes from blue to orange brown

49
Q

Name a polymer that was discovered by accident

Chemistry (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions