Production Of Materials

Front 1

Identify the industrial source of ethylene from the cracking of some of the fractions
from the refining of petroleum

Back 1

Due to the need for smaller hydrocarbons the larger ones can be cracked down into smaller
ones using special catalysts
- The catalyst used is called a zeolite
ƒ If it is not decomposed entirely the Hydrocarbons are further decomposed by steam cracking
− A mixture of alkanes with steam is passed through very hot metal tubes.

Front 2

Identify that ethylene, because of the high reactivity of its double bond, is readily
transformed into many useful products

Back 2

The double bond is where the reaction would occur
- Other atoms can be easily added when the double bond is broken

Front 3

Identify that ethylene serves as a monomer from which polymers are made

Back 3

The double bond breaks so that it can join to other ethylene.

Front 4

Identify polyethylene as an addition polymer and explain the meaning of this term

Back 4

The double bond opens up to form two single bonds that can bond with other things, this is
called an addition reaction

Front 5

Outline the steps in the production of polyethylene as an example of a commercially and
industrially important polymer

Back 5

Type 1
− high pressure (1000-3000Atmos) and high temperature(300oC) and an initiator
(organic peroxide, compound containing –O–O– group, some times oxygen is used)
− results in significant chain branching
− results in loosely packed material

Front 6

Identify the following as commercially significant monomers:
− vinyl chloride
− styrene
By both their systematic and common names

Back 6

Polyvinyl chloride or PVC or ploychloroethene
− used for insulation and drain pipes
− water resistant and doesn’t conduct

Front 7

Identify data, plan and perform a first-hand investigation to compare the reactivity of
appropriate alkenes with the corresponding alkanes in bromine water

Back 7

Due to the high reactivity of the double bond alkenes react fast with bromine water under UV
light
ƒ alkanes react very slowly under UV light
ƒ Equations for reaction with bromine water

Front 8

discuss the need for alternative sources of the compounds presently obtained from the
petrochemical industry

Back 8

Since the petrochemical industry relies of crude oil for its raw component
- Crude oil will run out in about 40 years
- Scientists argue that we should start using alternative sources such as obtaining ethanol from
fermentation.
- Others argue that as oil supplies diminish then costs will rise and it will eventually become
too expensive to use. Then, naturally, people will stop using oils and alternative fuels will
become more cost effective.
- Others say that remaining crude oil will be exclusively used for the petrochemical industry;
car will use solar power etc.

Front 9

explain what is meant by a condensation polymer

Back 9

Condensation polymers are polymers that form by the elimination of a small molecule (often
water) when pairs of monomers molecules join together

Front 10

describe the reaction involved when a condensation polymer is formed

Back 10

Glucose has the formula 6 12 6 C H O , it can be written as HO − C H O −OH 6 10 4
- When glucose joins together to form cellulose HO − C H O −OH 6 10 4 HO − C H O −OH 6 10 4
- a water is lost and two free bonds are formed to join the monomers together

Front 11

identify that cellulose contains the basic carbon-chain structures needed to build
petrochemicals and discuss its potential as a raw material

Back 11

Cellulose has 4 carbons joined in a chain so it would be regarded as the basic structure for making molecules for petrochemicals
- Cellulose has been used as the raw material for may biopolymers such as cellophane
- Biopolymers are biodegradable unlike traditional petrochemical polymers

Front 12

present data from secondary sources and analyse
progress in the recent development and use of a named biopolymer.

Back 12

Biopolymers are polymers that are made totally or in large part by living organisms

Front 13

describe the dehydration of ethanol to ethylene and identify the need for a catalyst in
this process and the catalyst used

Back 13

Using a concentrated Sulphuric acid catalyst ethanol can be turned into ethylene and water
with some heat

Front 14

describe the addition of water to ethylene resulting in the production of ethanol and
identify the need for a catalyst in this process and the catalyst used

Back 14

Using a dilute Sulphuric acid catalyst ethylene and water can be hydrated to ethanol with a
little heat.

Front 15

describe and account for the many uses of ethanol as a solvent for polar and non-polar
substances

Back 15

The C-O and H-O bonds in ethanol make it a polar molecule
- It is also able to form hydrogen bonds, this allows it to dissolve substances such as glucose
and sucrose
- Also has carbon chain so it can dissolve carbon chemicals such as hexane

Front 16

outline the use of ethanol as a fuel and explain why it can be called a renewable resource

Back 16

Ethanol is a hydrocarbon so it can combust to form H2O and CO2
- It can be created from biomass using a process called fermentation
- It is renewable since plants (biomass) use H2O and CO2 to grow

Front 17

describe conditions under which fermentation of sugars is promoted

Back 17

- Yeast is added
- Use simple sugars or starch
- Concentration of alcohol is less than 15%
- Kept at blood temperature (37°C)
- Air is excluded

Front 18

summarise the chemistry of the fermentation process

Back 18

− Under suitable conditions (described above) fermentation of sugars is carried out.
− ( ) 2 ( ) 2 ( ) 6 12 6 3 2 2 C H O aq Yeast→ CH − CH −OH aq + CO g
− Once the concentration of alcohol reaches 15% the solution must undergo fractional
distillation to continue fermentation (since the alcohol kills the yeast)
− Under typical industrial conditions concentrations of about 95% can be reached from
repeated fractional distillation

Front 19

define the molar heat of combustion of a compound and calculate the value for ethanol
from first-hand data

Back 19

-Molar heat of combustion is the energy released from 1 mole of substance combusting
completely
- same as minus the enthalpy change (ΔH)

Front 20

assess the potential of ethanol as an alternative fuel and discuss the advantages and
disadvantages of its use

Back 20

advantages
− renewable resource
− since it is water soluble it can be put out with water (risk analysis)

Front 21

identify the IUPAC nomenclature for straight-chained alkanols from C1 to C8

Back 21

− Same as alkenes but replace –ene with –anol.

Front 22

process information from secondary sources to summarise the use of ethanol as an
alternative car fuel, evaluating the success of current usage

Back 22

It is currently uneconomical to ferment ethanol specifically for use car fuel due to the high
cost of distillation.

Front 23

explain the displacement of metals from solution in terms of transfer of electrons

Back 23

A displacement reaction is a reaction in with a metal converts the ion of another metal to the
neutral atom
- For example, when copper displaces silver from solution
− Cu(s) + 2Ag + (aq)→2Ag(s) + Cu2+ (aq)
− Copper gives 2 silver atoms an electron each to displace them from solution

Front 24

identify the relationship between displacement of metal ions in solution by other metals
to the relative activity of metals

Back 24

The more active metals will displace the less active metals from solution

Front 25

account for changes in the oxidation state of species in terms of their loss or gain of
electrons

Back 25

For positive monatomic ions the oxidation state is the charge on the ion
- This changes, as there is a loss or gain of electrons. For example
− Fe2+ → Fe3+ + e− iron’s oxidation state goes from 2 to 3
− Sn4+ + 2e− → Sn2+ tin goes from 4 to 2
- To calculate oxidation state remember Oxygen is always -2
- For example, Fe2O3 would indicate Fe has oxidation state of +3

Front 26

describe and explain galvanic cells in terms of oxidation/reduction reactions

Back 26

Redox reactions involve the transfer of electrons from one reactant to another
- Galvanic cells make use of this transfer of electrons by placing the reactions at different
locations and allowing the electrons to pass through a wire
- For the copper-silver cell the reactions go like this
− Cu →Cu2+ + 2e− (Oxidation)
− Ag+ + e− → Ag (Reduction)
− Cu(s) + 2Ag+ (aq)→Cu2+ (aq) + 2Ag(s) (Redox)
- The electron released by the copper does work in the circuit before being given to the silver

Front 27

outline the construction of galvanic cells and trace the direction of electron flow

Back 27

- 2 electrodes (zinc, copper)
- 2 electrolytes (zinc nitrate, copper nitrate)
- salt bridge (potassium nitrate)
- In galvanic cell electrons go from oxidation to reduction (anode to cathode)
- Zinc is anode since it more readily oxidises

Front 28

define the terms anode, cathode, electrode and electrolyte to describe galvanic cells

Back 28

Anode: The conductor where oxidation occurs
- Cathode: The conductor where reduction occurs
- Electrode: A conductor where reduction or oxidation occurs (either and anode or cathode)
- Electrolyte: The medium where ions flow and is in contact with the Electrodes

Front 29

present information on the structure and chemistry of a dry cell or lead-acid
cell and evaluate it in comparison to one of the following:
− button cell
− fuel cell
− vanadium redox cell
− lithium cell
− liquid junction photovoltaic device (eg the Gratzel cell)

Back 29

Lead-acid cells are used in motor car batteries

Front 30

distinguish between stable and radioactive isotopes and describe the conditions under
which a nucleus is unstable

Back 30

radioactive isotopes emit radiation which can be detected
- and isotope is unstable
− if its atomic number is greater that 83
− if its ratio of neutrons to protons places it outside the zone of stability

Front 31

describe how transuranic elements are produced

Back 31

-










-






-






-

Front 32

describe how commercial radioisotopes are produced

Back 32

Molybdenum-99 is formed by putting special UO2 pellets in a reactor core

Front 33

identify instruments and processes that can be used to detect radiation

Back 33

Photographic film
− the radiation exposes the film like light

Front 34

identify one use of a named radioisotope:
− in industry

Back 34

Gamma radiation is effective in destroying biological molecules such as DNA it can be used
to destroy bacteria

Front 35

identify one use of a named radioisotope:
-in medicine

Back 35

technetium-99m is used in diagnosis since it only releases gamma radiation so it dose not
damage tissue much
- it is injected into the blood stream so that clots and other circulation disorders can be found
- it can also detect brain tumours
- it has short half life (6hours) so there is minimum damage to the patient