Hsc Chemistry

Front 1

S9.2.1.2
Catalytic Cracking

Back 1

The process in which high Molecular Weight fractions from crude oil are broken into lower Molecular weight substances in the presence of high temperatures and a catalyst.

Front 2

S9.2.1.2
Zeolites

Back 2

The inorganic compounds used as catalysts for cracking alkanes

Front 3

S9.2.1.2
Steam Thermal Cracking

Back 3

The process by which ethane gas or larger hydrocarbons are mixed with steam and passed through large metal coils, producing ethylene

Front 4

S9.2.1.2
Which alkene is a major by-product of catalytic cracking?

Back 4

Ethylene

Front 5

S9.2.1.2
Why is steam thermal cracking necessary?

Back 5

Catalytic cracking is not necessary to meet the needs of ethylene

Front 6

S9.2.1.3
What property makes alkenes more reactive than their corresponding alkanes?

Back 6

A Double bond

Front 7

S9.2.1.3
Addition Reaction

Back 7

A reaction in which two or more molecules are reacted together to form a single molecule

Front 8

S9.2.1.3
A substance reacting with an alkene through breaking open the double bond into two single bonds

Back 8

Addition Reaction

Front 9

S9.2.1.3
Product: Ethanol
- Reacants
- Conditions
- Uses

Back 9

Reactants - Ethylene and Water
Conditions -high pressure, ~300C
Uses - Fuel, Industrial, commercial and domestic solvent, Cleaning and disinfecting fluid

Front 10

S9.2.1.3
Product: Ethylene Oxide
- Reacants
- Conditions
- Uses

Back 10

Reactants - ethylene and Oxygen
Conditions - ~250C with silver as a catalyst
Uses - Fumigant

Front 11

S9.2.1.3
Product: Ethylene Glycol
- Reacants
- Conditions
- Uses

Back 11

Reactants - ethylene oxide and dilute acid
Conditions - treatment with dilute acid solution
Uses - anti-freeze liquid, manufacturing of polyester

Front 12

S9.2.1.3
Product: Vinyl Chloride
- Reacants
- Conditions
- Uses

Back 12

Reactants - Oxygen and chlorine
Conditions -~150C and copper chloride catalyst
Uses - monomer for producing polyvinyl chloride

Front 13

S9.2.1.4
Definition: Monomer

Back 13

A relatively simple molecule from which a polymer can be made

Front 14

S9.2.1.4
Definition: Polymer

Back 14

A large molecule in which one or more monomers are repeated

Front 15

S9.2.1.4
Definition: Polymerisation

Back 15

The reaction of monomers to form a polymer

Front 16

What polymer does ethylene form when it polymerises?

Back 16

Polyethylene

Front 17

S9.2.1.4
How does ethylene form a saturated polyethylene chain

Back 17

The double bond in ethylene breaks open to form single bonds with neighbouring ethylene molecules

Front 18

S9.2.1.5
Definition: Addition Polymer

Back 18

a polymer formed by molecules adding together without the loss of any atoms.

Front 19

S9.2.1.5
When an addition polymer is formed, what other product is formed as a by-product?

Back 19

None

Front 20

S9.2.1.5
Requirements needed to form Low Density Polyethylene (LDPE)

Back 20

High Pressure (1000-3000atm)
High Temp (300C)
An Initiator (usually an organic peroxide)

Front 21

S9.2.1.5
Polymerisation process of Low Density Polyethylene (LDPE)

Back 21

- Peroxide initiator splits to form free radicals
- Free radicals allows the initiation of the joining of ethylene monomers

Front 22

S9.2.1.5
In the polymerisation process of LDPE, why is the organic peroxide an initiator and not a catalyst

Back 22

Because the initiator is incorporated into the polymer

Front 23

S9.2.1.5
Branching of the polymer LDPE

Back 23

Significant chain branching

Front 24

S9.2.1.5
What effect does significant chain branching have on the packing of LDPE polymer chains?

Back 24

Chains cannot pack closely together or in an orderly way

Front 25

S9.2.1.5
What is the molecular weight of Low Density Polyethylene (LDPE)?

Back 25

Up to 1,000,000 g/mol