Chemistry – Production of materials notes
Chemistry Study
Yr 12 HSC
Production of Materials
1. Fossil fuels provide both energy and raw materials such as ethylene, for the
production of other substances
Identify the industrial source of ethylene from the cracking of some of the
fractions from the refining of petroleum
Petroleum is a mixture of hydrocarbons.
When petroleum undergoes fractional distillation, there is a higher demand for
some fractions due to their high economic value.
Other fractions, consisting of larger molecules of low value, can be cracked,
breaking the larger molecules (of a similar weight) into smaller molecules.
This is how ethylene/ethene is made in industry
Catalytic cracking: Achieved through high temperatures (500 degrees Celsius).
Zeolite catalyst. Ethylene is a valuable product of this reaction.
Example of catalytic cracking: C10H22(g)  C8H18(g) + C2H4(g)
Identify that ethylene, because of the high reactivity of its double bond, is readily
transformed into many useful products
Ethenes have double bonds
and therefore can be involved
in addition reactions. An
addition reaction is when there
are no atoms taken away, but there are atoms added. These reactions require a small
amount of energy but can be used to create many products.
Identify that ethylene serves as a monomer from which polymers are made
Monomer: a small molecule
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Polymer: a large molecule made up of a large number of identical monomers
joint in chains
Polymerisation: a chemical reaction in which many monomers form a chain called
a polymer
Ethylene/Ethene is one example of a monomer, a long chain of many of Ethene
monomers is called polyethene
Identify polyethylene as an addition polymer and explain the meaning of this term
Polyethylene is an addition polymer; this means it has been formed from an
addition reaction. Where no atoms are taken away, they are only added.
This is able to occur as a result of the double bond in ethane/enylene, when the
double bond is broken more atoms are can be added on without taking away any
atoms, due to the free electrons. The polymer is the only product created.
Outline the steps in the production of polyethylene as an example of a
commercially and industrially important polymer
Low Density Polyethylene, LDPE:
 An initiator known as a peroxide is used to pull an electron out of the
double bond
 Two extra carbon atoms are added to the chain
This is done at high temperatures and pressures.
The product is branched polythene:
This means the molecules are unable to pack closely together, so it is/has low density
 Low mp
 Relatively soft
High Density Polyethylene, HDPE:
 Transition metal catalysts are used
This is done at a lower temperature and pressure
The product is un-branched polyethylene:
This means the molecules can pack closely together so it is/has Hard/stiff
 Higher dencity
 Higher mp
Linear Low Density Polyethylene, LLDPE:
This is a method half way between HDPE and LDPE
 Metallocene molecules (metal ions sandwiched between two carbon based
rings) used as a catalyst
The product still has a large no. of side branches, but the branches are much
shorter
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Identify the following as commercially significant monomers:
Vinyl Chloride by both their systematic and common names
Vinyl Chloride/ chloroethene, is the monomer from which polyvinyl Chloride (PVC)
is made.
Styrene by both their systematic and common names
Styrene is the monomer from which Polystyrene is made.
Describe the uses of the polymers made from the above monomers in terms of
their properties
Vinyl Chloride/ chloroethene:glue and pipes
Styrene:
cups and
plates
2. Some scientists research the extraction of materials from biomass to reduce
our dependence on fossil fuels
Discuss the need for alternative sources of the compounds presently obtained
from the petrochemical industry
Petrochemical industry: industry that produces/uses petroleum as a raw material
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Petroleum originates from fossil fuels, there are a number of problems associated
with the use of fossil fuels:
 Fossil fuels are non-renewable, as a result of the growth in
consumption and the increased demand for these resources grow, it
has been estimated that many of these will fun out within our
generation. Probably between 2025 and 2070
 Fossil fuels have a negative impact on the atmosphere, releasing
gasses that contribute to the greenhouse effect
Due to these reasons it is important that we become less dependent on Petroleum
and use alternate sources of energy, as well as alternate substances that can be
used to produce mate rials such as polyethene.
From CSU (just know a few statistics):
Petrochemicals are chemicals made from compounds in petroleum or natural gas.
Currently Australia has petroleum reserves that will last about ten years and
natural gas reserves that will last about one hundred years. Fossil fuels have taken
hundreds of millions of years to accumulate. Over 95% of fossil fuel is burnt as a
source of energy and once burnt, fossil fuels are no longer available. Less than 5%
of fossil fuel is used to make plastics and only a small percentage of that plastic is
recycled. If energy and material needs are to be met in the future, alternative
sources will be needed as fossil fuel sources are used up.
Explain what is meant by a condensation polymer
Condensation Polymer: when monomers react to form polymers, small molecules
are also formed, often water
Describe the reaction involved when a condensation polymer is formed
Condensation
Similarities
Addition
Joining of monometers
Differences
to form Polymers
No double bond necessary
Double bond necessary
Products: Polymer and small
molecule
Products: polymer
Describe the structure of cellulose and identify it as an example of a condensation
polymer found as a major component of biomass
Biomass: material produced by living organisms
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Cellulose is a major component of biomass
Monomer- glucose  Polymer- cellulose
When glucose monomers join to form cellulose they also form water. This makes
cellulose a condensation polymer.
The glucose monomers are linked in strong covalent bonds, there are also
hydrogen bonds, so cellulose is:
 Linear
 Strong
 Rigid
 Chemically stable

Identify that cellulose contains the basic carbon-chain structures
needed to build petrochemicals and discuss its potential as a raw
material

Cellulose could be used to make some chemicals we currently get
from crude oil

There are large amounts of cellulose left over from agricultural
processes. These are usually burnt, berried or composted.

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Cellulose  Glucose
Enzymes called cellulase break down the microscopic structure of
cellulose
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Glucose  Ethanol
This is done by yeast, in a process known as fermentation
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Ethanol  Ethylene
Fermentation can be heated in the absence of oxygen to form
ethylene and water
Advantage
 Cellulose can be obtained from structures that are currently thrown away,
and are difficult to dispose of
 Cellulose is a renewable resource

Disadvantages
Much of the energy is required for this process comes from oil, using more oil
than would be used to crack oil to ethylene
 More expensive
 Ethical problems- using crops to make plastics while people are starving
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Use available evidence to gather and present data from secondary
sources and analyse progress in the recent development and use of a
named biopolymer (Polyhydroxyalkanoate PHAs) This analysis should
name the specific enzyme (bacteria) used or organism used to
synthesise the material and an evaluation of the use or potential use
(see below) of the polymer produced related to its properties
Polyhydroxyalkanoate Polymers (PHAs): naturally-occurring polymers
produced by bacteria.
 Work is underway to determine if they can be grown inside genetically
modified plants

How is it produced:
There are two methods of production
 They are produced by bacteria and can be extracted and processed for many
uses.
 Genetically-modifying plants to produce PHAs.
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Organism or enzyme used to synthesise the biopolymer:
Bacteria
Uses:
The biopolymers polyhydroxyalkanoate are used in many applications,
including:
 molded goods
 adhesives,
 paper coatings
 films
 non-woven fabrics
 polymer performance additives
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PHAs could replace a significant proportion of the petroleum used today
Why is its production important for society and for the environment?
It is a new and another way of forming everyday objects that society use such
as plastics and could possibly replace a large amount of petroleum.
 This is important for the environment as the petroleum is running out and has
negitive environmental affects.

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Benefits include:
Development of PHA polymers that compete economically with conventional
fossil-based polymers
 Improved performance of other biobased polymers through blending with
PHAs
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Are there limitations to its commercial viability in the short term?
Researchers are still trying to determine whether it can be developed or
grown inside genetically modified plants.
 They are focused on developing processes for producing PHAs that can
compete with conventional fossil-based polymers. This includes developing
improved technologies to extract and process PHAs and PHA blends.
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Researchers will also study the fundamental polymer properties of PHA
polymers and their blends.
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Poly(hydroxybutanoate) PHB
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Properties:
Stiff
Brittle
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History:
Maurice Limoigne first produced PHB in 1925
How is it produced:
PHB can be produced in the lab by feeding bacteria a diet rich nurturance
until large colonies form and then withdrawing glucose. The bacteria
automatically start secreting PHB which provides them with an energy store.
 In the 1980’s the three genes in Alcaligenes eutrophus needed for the
production of PHB were successfully cloned and transferred into E.coli, a
common bacteria that was well-researched, reproduced quickly and had an
easily manipulated physiology.
 Cargill Dow transported the PHB gene into corn and maize plants and allowed
crops of PHB-producing plants to be grown and harvested.


Uses:
It was first introduced into the medical industry, to make non-toxic and
decomposable structures, and to make plastics in the chemical engineering
industry.
 Monsanto first put PHB on the shelves in the form of shampoo bottles, but
due to costs this was unsuccessful. It could be potentially successful in plastic
bags and containers.

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Benefits include:
Biodegradable
Renewable
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Are there limitations to its commercial viability in the short term?
Expensive

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Why is its production important for society and for the environment?
It could be used to replace petroleum
New research:
For PHBs to be successful it must be able to be produced for less money than
petroleum-based alternatives.
 Cargill Dow are currently working on the biopolymer being produced by
plants. This could well be the way of the future if they can produce something
that is cost effective and maintain the useful properties of the compound.
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3. Other resources, such as ethanol, are readily available from renewable
resources such as plants
Describe the dehydration of ethanol to ethylene and identify the need for a
catalyst in this process and the catalyst used
 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
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Alkanoles: alkanes with one H atom replaced by an OH group
The number prefix tells of the location of the OH group
Hydration: the process
by which the OH group
is added to an alkane
 Dehydration: the
process by which the
OH group is removed
from the alkanol

The catalyst used in this
process is sulphuric
acid/ H2SO4.
Describe and account for the many uses of ethanol as a solvent for polar and
non-polar substances
Ethanol is a good solvent for both polar and non-polar substances
Ethanol is used as a solvent in:
Paints
Inks
Food colouring
Perfumes
This is because:
C-O and H-O bonds are polar
CH3 – CH2 bonds are non polar
Ethanol can therefore dissolve both polar and non-polar substance
Outline the use of ethanol as a fuel and explain why it can be called a
renewable resource
Ethanol can be used as a fuel as it combusts in oxygen to release CO2 H20 and
heat.
Ethanol can be made from plant material and the products of its combustion,
carbon dioxide and water, are the reactants needed by plants for
photosynthesis, and it can replace itself within the time span of a human life
time.
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Describe conditions under which fermentation of sugars is promoted
Summarise the chemistry of the fermentation process
Fermentation must occur with/in:
An anoxic environment (no free oxygen)
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Yeast acts as a catalyst
Glucose is ground up with water in an aqueous form
C. 37 o C
C6H12O6(aq)
2C2H6O +2CO2
Glucose
ethanol(15%) + Carbon dioxide

Define the molar heat of combustion of a compound and calculate the value
for ethanol from first-hand data

Molar heat of combustion- the energy released when 1 mol of a substance
undergoes complete combustion in a plentiful supply of oxygen
ΔH=-mc Δ T
ΔH- change in heat (Joules)
m- the mass of water that is heated (g)
c- heat capacity of water (4.18JK-1g-1
ΔT- change in temperature
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To then find the molar heat of combustion
= ΔH

n
 Or to find the amount of Kj/g
= ΔH

g (of the water heated????)
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Assess the potential of ethanol as an alternative fuel and discuss the
advantages and disadvantages of its use

Advantages

Disadvantages

Renewable

Large amounts of arable land

Makes sugar production more
viable

Does not produce as much
energy as octane

Less likely to undergo
incomplete combustion so less
CO emissions

Corrodes car engines if used with
more than 10% ethanol

Extend supply of petrol

High cost of distillation

Does not add to the Carbon
cycle
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Identify the IUPAC nomenclature for straight-chained alkanols from C1 to C8
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Meth
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Eth
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Prop
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But
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Pent
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Hex
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Hept
1
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2
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3
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4
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5
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6
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7
 Oct
8
 Process information from secondary sources to summarise the processes
involved in the industrial production of ethanol from sugar cane
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Process information from secondary sources to summarise the use of ethanol
as an alternative car fuel, evaluating the success of current usage
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Today:
10% of Brazils total energy usage is provided by ethanol
In Australia ethanol is mixed with petrol (usually no more than 10%)

Present information from secondary sources by writing a balanced equation
for the fermentation of glucose to ethanol

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C6H12O6(aq)
2C2H6O +2CO2
Glucose
ethanol(15%) + Carbon dioxide

4. Oxidation-reduction reactions are increasingly important as a source of
energy

Explain the displacement of metals from solution in terms of transfer of
electrons

More active metals displace less active metals in a solution.


The more active metal looses electrons (oxidation)
The least active metal gains electrons (reduction)

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For example:
If an iron nail is placed in a solution of blue copper (II) salt, some of the iron
nails dissolves.
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
At the same time, the blue colour of Cu2+ ions disappears and a dark copper
coating appears on the nail surface.

The overall reaction is-

Identify the relationship
between displacement
of metal ions in solution
by other metals to the
relative activity of
metals
A metal higher on the activity series will react when placed in a solution
containing a metal lower on the reactivity series. The less active metal being
displaced.
 The larger the gap in the reactivity series between the metals the more
reactive they are
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For example:
the metals from K to Pb react with dilute acids releasing hydrogen gas
the metals from K to Mg react with liquid water
the metals from Al to Ni require water to be in the form of steam before
reacting.
Account for changes in the oxidation state of species in terms of their loss or
gain of electrons
 Note- there has never been a question in the HSC on oxidation no, but still
have to know
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Oxidation state/ oxidation number:
An imaginary number that allows us to see if oxidation or reduction has
occurred.

When a metal reacts with dilute acid and releases hydrogen, the metal
undergoes oxidation (loss of electrons) while the hydrogen ions in the acid
undergo reduction (gain of electrons).

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Example:
Magnesium changes from oxidation state 0 to 2. This is an increase, thus this
is oxidation. Hydrogen changes oxidation state from +1 (in H+) to 0 (in the
element H2). This is a decrease, thus this is reduction.
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
It is important to recognise that when a substance acts as a reductant,
causing reduction, it is oxidised. When a substance acts as an oxidant, causing
oxidation, it is reduced.
There are a few rules that are required while finding the oxidation state.
 For monatomic atoms the oxidation number is the charge of the ion
 For a neutral molecule the oxidation state is zero
 For ions the oxidation state is equal to their overall charge
 Flourine is always -1 unless it is with halogens or oxygen when it can be
positive
 Hydrogen is always +1 except with metal hydrides (e.g. LiH)
 Oxygen is -2 except With Flourine
 In peroxide compounds where it is -1
 e.g.
 H2O
 NH4=

H= +1

N=-3

O= 
H=+4
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Describe and explain galvanic cells in terms of oxidation/reduction reactions

Galvanic cells are electrochemical cells, they are an arrangement of chemicals
and equipment that allows a redox reaction to occur. It physically separates the
reductant and oxidant.

Outline the construction of galvanic cells and trace the direction of electron flow

Define the terms anode, cathode, electrode and electrolyte to describe galvanic
cells
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Electrolyte- a chemical that in a solution or molten form conducts eElectrodes- a material transferring electrons to and form an electrolyte solution
(graphite and platinum are inert)
 Anode- oxidation and negative electrode
 Cathode- reduction and positive electrode
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Gather and 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:
Ty
p
e
©

Che
mist
ry

Uses
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Note
s
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Cost
and
practi
cality

Impact
on
society

Impact
on
environm
ent
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
Ano  Torch
de:
batterie
Zn
s
 Zn
 Radios
Zn2++2e-  Calculat
ors
 Cath
ode:
Carb
on
rod
emb
edd
ed
in
past
e
 2Mn
O2 +
2NH
2+
4 +
2eMn2O3
+ 2NH3 +
H2 O

Dry
cell

Onc
e
the
mat
erial
s are
used
up
they
stop
work
ing

Elect
rolyt
e:
Mn
O2,
ZnCl
2,
NH4
Cl,
wat
er
past
e
 Ano  Camera  The
de:
s
batt
Zn  Heart
ery
 Zn +
pacem
‘dies
2OH
akers
’
 Hearin
whe
ZnO +
g aid
n
H2 O +
the
2e
Zn

C
heap,
small,
reliable,
easy to
use,
portable,

No
negative
impact
No
pollution
issue
 Zn and
Mn are
both
used by
plants


1.5V no
matter
what size
they are


But
ton
Cell
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Ag2O  Hearing
is
aids and
expen
pacemaker
sive,
s can be
 ZnO is
small and
in
compact
powd  Expensive,
er
so not
form

13 of 18

No
negative
affect
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Cath
ode:
Ag
 Ag2
O+
H2 O
+ 2e
2Ag +
2OH Elect
rolyt
e:
KOH



runs
out.
Som
e
can
be
rech
arge
d by
forci
ng
the
reac
tion
into
reve
rse
do
has a
large
SA
and ..

.
produ
ces
more
energ
y
available
to all
Solve problems and analyse information to calculate the potential
requirement of named electrochemical processes using tables of standard
potentials and half-equations

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E : Standard reduction electrode potential, the tendency of species to gain
electrons by comparison to hydrogen
o
Table of standard Potentials
 The numbers indicate the tendency of species to be reduced (gain e-). If the
number is negative the species is oxidised (gain e-). The more positive the
number the greater the tendency of the reaction to occur

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e.g.
Cu(s) + 2Ag+(aq) Cu2+(aq) + 2Ag(s)
The half reactions and their Eovalues areCu(s) Cu2+(aq) + 2eEo=0.34
2Ag+(aq) +2e- Ag(s)
Eo=0.80
Total= 0.46

5. Nuclear chemistry provides a range of materials

Distinguish between stable and radioactive isotopes and describe the conditions
under which a nucleus is unstable

A unstable isotope is one that emits radiation

An isotope is unstable if:
 It’s atomic number (z) is greater than 83
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It’s ration of neutrons to protons places it outside the zone of satiability
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Describe how
transuranic elements are produced

Transuranic elements are elements with a greater atomic number (z) than
uranium i.e. >92

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To increase the mass number and the atomic number we need to add mass to
the original nucleus.
 One way of doing this is to add neutrons or possible larger particles such as He
nuclei 42He

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This can be done in two ways:
1. With a nuclear reactor where plenty of neutrons are flying about, these
bombard other nuclei
2. By accelerating mass, e.g. 42He nuclei into other nuclei into other nuclei, this
is done in an accelerator called a cyclotron. A cyclotron is useful in the
production of nuclei with a short half life

Linear accelerators can also be used though they are not as
convenient as having an on-site cyclotron at a hospital (they are used to
diagnose disease)

Note: the nucleus that is bombarded must not be fissile- meaning it must not be
able to split as in a fission reaction.
 e.g. 235U will split because it is fissile
 238U will not split because it is not fissile
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e.g. in a reactor 238U is bombarded with neutrons. Write out the nuclear reaction.

Hint- 23992U is unstable and emits ß particles
U + 10N

Describe how commercial radioisotopes are produced

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Many synthetic radioisotopes are made in reactors
About 20 of these are useful in medicine and industry
Many are made using reactors as a neutron source
©
92
238
93
Np + 0-1e-
239
92
239
U
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e.g. Cobalt-59 is used to make Cobalt-60
59
1
60

27Co + 0n
27Co
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Some products of fission:
Technium-99 is an isotope used in medical diagnosis
It’s preparation is as followed

Uranium- 235

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Fission in a reactor

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 Molybdenum-99
(long-ish half life. This is useful in transportation to a hospital)

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Decays continuously to Technetium-99

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99
Tc is extracted by running a saline solution through the 99Mo

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Used in diagnosis
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Medical radioisotopes are also produced on-site in cyclotrons
i.e. the target substance in bombarded with nuclei
Iodine-123 is made in a cyclotron

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Identify instruments and processes that can be used to detect radiation
Detection of radiation:

Ways to detection include Photographic film- the film darkens when hit by radiation
 Cloud chambers- radiation ionises the air and ‘jet streams’ occur
 Geiger- Müller counter- detects from ionisation (caused by radiation) makes a
pulse which is amplified
 Scintillation counter- radiation hits particles and causes flashes of light. These
are amplified to make a signal
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Identify one use of a named radioisotope:
In industry
Cobalt-60
In medicine
Technetium-99
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Describe the way in which the above named industrial and medical radioisotopes
are used and explain their use in terms of their properties
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Cobalt-60:
Industrial radiograph- to inspect metal parts and welds for defects.
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Beams of radiation are directed at the object to be checked. More radiation will
pass through if there are cracks, breaks, or other flaws in the metal parts and will
be recorded on the film.
 Properties Co-60 has a half-life of 5.3 years and can be used in a chemically inert form held
inside a sealed container. This enables the equipment to have a long lifetime and
not require regular maintenance.
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Technetium-99m:
Is used in over half of the current nuclear medicine procedures, such as
pinpointing brain tumours.
PropertiesIt has a very short half-life of 6 hours
It emits low energy gamma radiation that minimises damage to tissues but can
still be detected in a person's body by a gamma ray sensitive camera
It is quickly eliminated from the body
It is reasonably reactive; it can be reacted to form a compound with chemical
properties that leads to concentration in the organ of interest such as the heart,
liver, lungs or thyroid.

Process information from secondary sources to describe recent discoveries of
elements

In January 2010 scientists successfully formed the new element Ununseptium
(z=117)
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To creating just 22 milligrams of berkelium took 250 days. To discover
Ununseptium two collisions were run, colliding calcium atoms into the berkelium,
each taking 70 days. This process created six atoms of Ununseptium.
 The Ununseptium lasted only a fraction of a second
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Ununseptium is a placer name for element 117, it will change once the element is
confirmed.
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Use available evidence to analyse benefits and problems associated with the use
of radioactive isotopes in identified industries and medicine
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Cobalt-60:
Benefits Able to sterilise items that would be damaged by heat-sterilisation
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Able to extend the half life of foods that have been damaged in this mannor
Has a relitivly long half life so requires little maintenance
 Problems There are radioactive wastes produced during it’s production
 It is difficult to dispose of spent Co-60
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Technetium-99:
Benefits Relatively short half life so leaves the body fairly quickly
 Emmits low Betta radiation so minimises damage to tissue but is still
detectable by a gamma sensitive camera
 Problems High cost
 Harms living cells
 Radioactive waste
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