POM 9.2.1 Flashcards

0
Q

Acid + Metal —> ?

A

Salt + Hydrogen gas

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

Acid + Base —–> ?

A

Salt + Water

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

Acid + Carbonate –> ?

A

Carbon dioxide gas + salt + water

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

Cracking of PENTANE reaction

A

Pentane (g) –energy–> ethylene (g) + propane (g)

C5H12 (g) –energy–> C2H4 (g) + C3H8 (g)

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

Hydrogenation of ethylene

A

Ethylene (g) + Hydrogen (g) –Pt–> Ethane (g)

C2H4 (g) + H2 (g) –Pt–> C2H6 (g)

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

Hydration of ethylene

A

Ethylene (g) + H2o (l) –H3PO4–> Ethanol (l)

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

Dehydration of ethanol

A

Ethanol (l) –H2SO4–> Ethylene (g) + H2o (l)

C2H5OH (l) –H2SO4–> C2H4 (g) + H2o (l)

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

Fermentation of glucose

A

Glucose (aq) –yeast–> ethanol (aq) + carbon dioxide (g)

C6H12O6 (aq) –yeast–> 2C2H5OH (aq) + 2CO2 (g)

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

Displacement of Cu from solution due to Zn

A

Zinc + copper sulfate –> zinc sulfate + copper

Zn (s) + CuSO4 (aq) –> ZnSO4 (aq) + Cu (s)

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

Ionic equation of Cu and Zn displacement

A

Zn + Cu (II) sulfate ion + Sulfate ion –> Zinc (II) ion + sulfate ion + Cu
Zn + Cu 2+ + SO4 2- –> Zn 2+ + SO4 2- + Cu

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

Net ionic equation for displacement of Cu from Zn

A

Zinc + Copper (II) ion —> Zinc (II) ion + Copper

Zn (s) + Cu 2+ (aq) —> Zn 2+ (aq) + Cu (s)

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

Half-equations of displacement of Cu from Zn

A
  • Zn —> Zn 2+ + 2e-

- Cu 2+ + 2e- —> Cu

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

Define an ALKANE

A

A hydrocarbon with only single bonds between the carbons

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

Define an ALKENE

A

A hydrocarbon with 1 or more double bonds between carbons

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

What is petroleum?

A

A complex mixture of hydrocarbons consisting mainly of alkanes and some alkenes

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

What is Ethylene? What is it’s systematic name and formula?

A
  • Systematic name: Ethene
  • Formula: C2H4
  • One of the most useful substances in the petrochemical industry
  • High demand
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the process of CRACKING?

A
  • The process of breaking large hydrocarbon molecules into smaller length chains, using heat (A)
  • Catalytic cracking
  • Thermal cracking
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How is CRUDE OIL separated?

A

Fractional distillation

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

Describe CATALYTIC CRACKING

A
  • Carried out in a “cat-cracker”
  • Long ALKANE molecules (C15-C25) are broken into an ALKANE and an ALKENE
  • Catalyst used: ZEOLITES
  • Carried out at 500’C
  • Absence of air
  • Pressure above atmospheric pressure
  • Uses less heat than thermal cracking but it is insufficient cause it can’t decompose large molecules completely
19
Q

Describe THERMAL (steam) CRACKING

A
  • No catalyst
  • Alkanes are decomposed COMPLETELY
  • Long-chain alkanes passed through metal tubes at 700’C - 1000’C
  • Pressure above atmospheric
  • Use of steam allows easy flow of hydrocarbon gases and removes carbon desposits
20
Q

Why is ETHYLENE highly reactive?

A
  • Ethylene has a highly reactive double-bond
  • It is a site of high electron density
  • One of the bonds readily breaks, creating 2 new bonding sites
21
Q

What are ADDITION reactions?

A
  • A type of reaction ethylene can undergo

- One bond in the double bond is broken and two atoms in a DIATOMIC molecule are ‘added on’

22
Q

What are the different types of addition reactions?

A
  • Hydrogenation: Ethylene + Hydrogen –Pt–> Ethane
  • Hydration: Ethylene + Water –H3PO4–> Ethanol
  • Halogenation: Reactive molecules from the halon group (Fl2, Cl2, Br2) can all react with ethylene
23
Q

Describe POLYMERISATION

A

The chemical reaction in which many identical small molecules combine to form one large molecule

24
Q

Differentiate between monomers and polymers

A
  • Monomers are the small identical molecules

- A polymer is the large molecule formed from many monomers

25
Q

Why can ethylene undergo polymerisation?

A

Because of its reactive double bond

26
Q

What is the monomer and polymer in ethylene

A
  • Monomer: Ethylene

- Polymer: Polyethylene

27
Q

Describe Addition polymerisation

A
  • No additional molecules are produced
  • There is no gain/loss of atoms
  • The double bond simply ‘opens’ and monomers attach
28
Q

Describe the high pressure method in the production of polyethylene

A
  • Ethylene subjected to pressures of 100-300MPa
  • Temperatures of 300’C
  • An initiator used (peroxide)
  • Creates UNBRANCHED chains of polyethylene which does not pack together tightly
  • LDPE
29
Q

Describe the Ziegler-Natta Process in the production of polyethylene

A
  • A few atmospheres of pressure
  • Temperatures of 60’C
  • Catalyst used
  • Creates UNBRANCHED chains of polyethylene which pack together densely
  • HDPE
30
Q

What are the steps in the production of polyethylene?

A
  • Initiation: the initiation molecule is added which reacts with one ethylene molecule, breaking the double bond and attaches to one bonding site, thus creating an ethylene initiator radical
  • Propagation: Another ethylene monomer attaches to this radical and this continues
  • Termination: The reaction stops when two such chains collide and the 2 radicals react, forming a longer chain
31
Q

Describe Vinyl Chloride and it’s systematic name and formula

A
  • Systematic name: Chloroethene
  • Formula: C2H3Cl
  • One hydrogen is substituted with a chlorine atom
  • Can form Polyvinyl Chloride
32
Q

Describe Styrene and it’s systematic name and formula

A
  • Systematic name: Phenylethene
  • Formula: C8H8
  • One hydrogen atom replaced by a benzene ring
  • Forms Polystyrene
33
Q

Use of LDPE in relation to its properties?

A

Plastic cling wrap - it is flexible, clear and non-toxic

34
Q

Use of HDPE in relation to its properties?

A

Rubbish bins - it is rigid, only slightly flexible and hard

35
Q

Use of Polyvinyl Chloride (PVC) in relation to its properties?

A

Garden hoses - it can contain UV inhibitors, it’s flexible and is relatively un-reactive

36
Q

Use of Crystal Polystyrene in relation to its properties?

A

CD cases - it is clear, hard, rigid, easily shaped and a good insulator

37
Q

Use of Expanded Polystyrene in relation to its properties

A

Disposable cups - it is light, cheap and a thermal insulator

38
Q

Which alkene and alkane were used to compare the reactivities of?

A

Cyclohexene and cyclohexane

39
Q

What was the conclusion of the bromine water experiment?

A
  • Cyclohexene turned the brome water colourless
  • Cyclohexane solution remained yellow
  • Thus, only cyclohexene reacted and therefore the alkene is said to be more active due to the double bond
40
Q

Formula for the bromine water experiment

A

C6H10 (l) + Br2 (aq) + H2o (l) —–> C6h10BrOH (l) + HBr (aq)

41
Q

Why was cyclohexene and cyclohexane used?

A
  • Ethylene/propene weren’t used because C1 - C4 are gases at room temperature - hard to manage
  • Cyclohexene is liquid at room temperature
42
Q

Limitations of the bromine water test?

A

The alkane reacted slightly as UV radiation caused slow substitution reactions

43
Q

Safety precautions of the bromine water experiment

A
  • cyclohexene/ane are poisonous if ingested and both give off fumes as they are highly volatile and flammable (use in fume cupboard)
44
Q

Limitations of the modelling of polymerisation practical

A
  • The model only provided a limited section of a polyethylene molecule as there were limited numbers of kits
  • The use of catalysts were not shown in the process - therefore less accurate