Chapter 1 – Production
of Materials
By: Raymond Chen
Chapter 1 – Production of Materials
1.1 – FOSSIL FUELS PROVIDE BOTH ENERGY AND RAW MATERIALS SUCH AS ETHYLENE, FOR THE
PRODUCTION OF OTHER SUBSTANCES
1.1.1 – INDUSTRIAL SOURCES OF ETHYLENE
Petroleum is a mixture of hydrocarbons that consists of liquid crude oil and natural gas but can only be separated
out via physical and chemical changes into simpler molecules like ethylene. Fractional distillation is used to
separate the liquid crude oil into different fractions containing molecules with similar molecular weight.By
breaking the covalent bonds in larger molecules, smaller and more useful molecules can be obtained.
Ethylene is one of the products with its simple structure a popular starting point for making a large number of
synthetic organic compounds. Thermal cracking (high temperatures) is used to crack large molecules, but the
energy costs that incur are reduced by using a catalyst (catalytic cracking). Catalysts including, silicon and
aluminium oxides or powdered zeolite (porous aluminium silicate) can reduced temperatures needed for
cracking to around 500C.
The catalyst used and the temperature during the cracking process determines the product produced.
𝐶2 𝐻6 (𝑔) → 𝐶𝐻2 𝐶𝐻2 (𝑔) + 𝐻2 (𝑔)
𝐶3 𝐻8 (𝑔) → 𝐶𝐻2 𝐶𝐻2 (𝑔) + 𝐶𝐻4 (𝑔)
1.1.2 – USES OF ETHYLENE
Unsaturated are fairly reactive when compared to saturated hydrocarbons due to the presence of a double
bond. Ethylene can be used in solvents pharmaceuticals, explosives, plastics, insecticides and many industrial
chemicals due to the presence of a double bond allowing for quick reactions. The double bond in ethylene is
used by chemists where the bond is broken and an atom is “added to” or bonded with each of the carbon
atoms. Water can be added in this way to produce ethanol.
This is done through absorbing ethylene in concentrated sulfuric acid at 70-100C then hydrolysing the mixture
by diluting with water; or it can be converted via catalytic hydration where ethylene and steam are passed over a
solid phosphoric acid catalyst. Ethanol is used in pharmaceuticals and as anti-freeze and as a cheaper alternative
to petrol.
Oxidisation of ethanol leads to the production of acetaldehyde (ethanal) and acetic acid (ethanoic acid).
𝑐𝑎𝑡𝑎𝑙𝑦𝑠𝑡,𝑂2
𝐶2 𝐻3 𝐶2 𝐻2 𝑂𝐻 →
𝑐𝑎𝑡𝑎𝑙𝑦𝑠𝑡,𝑂2
𝐶𝐻3 𝐶𝐻𝑂 →
𝐶𝐻3 𝐶𝑂𝑂𝐻
About half of the ethanol is converted to acetaldehyde and acetic acid that are used to produce other
substances.
1.1.3 – ETHYLENE CAN BE A MONOMER
The longer the alkane chain, the higher the melting point due to greater effect of dispersion forces as a result of
the large molecular size and surface area contact.By adding side chains and other function groups chemists can
change their properties and chemical reactiveness.
Ethylene is one a monomer that can be polymerised with the double bond in ethylene being broken and links
being made between the monomer units. Repetition can lead polymers of hundreds and thousands monomers
to be formed, this is known as polymerisation.
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By: Raymond Chen
Chapter 1 – Production of Materials
1.1.4 – POLYETHYLENE IS AN ADDITION POLYMER
The chain beginning the formation occurs when two ethylene molecules combine in the presence of a suitable
catalyst.
There are free electrons at the ends of carbon atoms hence they are able to add more ethylene molecules, hence
lengthening the chain. The end result is a plastic known as polyethylene. This process of linking ethylene is
known as addition polymerisation. The formula for polyethylene is 𝐶𝐻3 (𝐶𝐻2 )𝑛 𝐶𝐻3 .
Another type of polymerisation is condensation polymerisation where a simple molecule (generally water) is
eliminated between functional groups. This general occurs in –OH and –COOH groups.
1.1.5 – PRODUCING POLYETHYLENE
There are two main types of polyethylene: low density polyethylene (LDPE) and high density polyethylene
(HDPE).
LDPE:
Are produced in high temperatures at high pressures in the presence of oxygen or an organic peroxide,
producing free radicals in the monomer allowing for addition polymerisation. LDPE have short branches every 50
molecules and one or two long branches every molecule, these branches disrupt the regular close packing of
chains of polyethylene hence the low density. Due to the weak dispersion forces LDPE has a low melting point, it
is soft, tough, flexible, and translucent and of high purity. It can be easily melted and moulded in film wrap,
sandwich bags, plastic bags and plastic squeeze bottles.
HDPE:
Is made is the presence of a certain metal oxide at temperatures just above 300C at normal room temperature,
forming a relatively unbranched polymer. With few or no side chains, the long chains are almost linear and pack
closely together. These high dispersion forces produce a crystalline structure with higher melting points. It is
chemically resistant, hence used in petrol tanks, rubbish bins, plastic crates and agricultural piping.
1.1.6 – VINYL CHLORIDE AND STYRENE ARE IMPORTANT MONOMERS
Vinyl chloride or Chloroethylene
Vinyl chloride or chloroethylene is produced from ethylene via a substitution reaction with the substitution of
chlorine. Polymerisation can lead to the creation of polyvinylchloride (PVC). PVC is a thermoplastic and additives
are required to alter its flexibility and to resist degradation by UV rays. It is used in floor tiles, roofing and credit
cards. It is toxic when burned as it produced hydrogen chloride.
Styrene:
Styrene is produced from ethylene via an addition reaction with the presence of a phenyl group, 𝐶6 𝐻5 −, forming
a benzene ring with one hydrogen atom. Polystyrene is produced via polymerisation. Polystyrene is a hard,
transparent polymer and is used to produce food containers, packaging and plastic cups. By blowing air through
the polystyrene before it sets produces polystyrene foam. It is light and very good thermal insulators suitable
for foam drinking cups and hot food containers. Dissolving rubber into polystyrene makes it much more impact
resistant.
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By: Raymond Chen
Chapter 1 – Production of Materials
1.2 – SOME SCIENTISTS RESEARCH THE EXTRACTION OF MATERIALS FROM BIOMASS TO REDUCE
OUR DEPENDENCE ON FOSSIL FUELS
1.2.2 – ALTERNATIVE SOURCES FOR RESOURCES
Petroleum contribute to more than 80% of all transport needs and as the population grows, so will the demand
and as demands outgrows supply, the cost of petrol will go up, notwithstanding that petroleum is a nonrenewable source.
Australia has reserves of coal that can be used as an alternative fuel. But last one to two centuries, even if the
inefficiency of obtaining hydrocarbons from is coal is overcome, it is only a matter of time before the reserves
are depleted and another alternative source would have to be found. An alternative source of fuel that is actively
being researched is biomass which includes, wood and other plant matter, animal wastes and organic household
refuse.
Carbohydrate is an organic compound that is common in plants. Carbohydrates contain a polymer called
cellulose, from which ethanol can be fermented. E10 is an ethanol based fuel that is added to petrol and is
viewed to be positive for the environment. Ethanol is fermented in poor countries and used as fuel. Ethylene can
also be produced from ethanol.
As reserves of fossil fuels are depleted, experiments are taking place to grow biomass in previously arid
landscapes and develop fast-growing plants to ferment into ethanol. By using photosynthesis plants can be
harvested and new crops planted.
1.2.2 – CONDENSATION POLYMERS
Condensation polymers are formed such that when they are added together like an addition polymer, a
molecule, usually water, is released.However in the case of a condensation polymer two or three monomers are
incorporated in a chain.
The end of the condensation polymerisation depends on the number of functional end groups of the monomer
that can react:



One reactive group  Terminate
Two reactive groups  Linear polymer is formed
Three or more reactive end groups  3D, cross-linked polymer is made
Condensation polymers include:


Polyesters and nylon (artificial)
Natural polymers include, carbohydrates, proteins, cutin and silk.
Unlike addition polymers, condensation polymers are biodegradable with acid catalysts or bacterial enzymes
breaking the polymer chain into smaller units by hydrolysing the peptide or ester bonds between monomers.
1.2.3 – REACTIONS FORMING CONDENSATION POLYMERS
Nylon is made by reaction diamines with carboxyl derivatives such as dicarboxylic acid. As a pair of monomers
join together, a molecule of water splits out.
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By: Raymond Chen
Chapter 1 – Production of Materials
1.2.4 – CELLULOSE AS A CONDENSATION POLYMER
Cellulose (C6H10O5)n is a long chain of linked glucose sugar molecules found in higher plants. It is a common
component of cell walls and is most commonly used in textiles and paper. Cotton is the most pure form of
cellulose. Cellulose is a natural condensation polymer made by linking -glucose, with water being removed. glucose is a monosaccharide, through polymerisation it becomes polysaccharide. Cellulose is found in wood pulp
and cotton. Polysaccharide form rings and hydrogen bonds, they are packed in a regular pattern, hence forming
stable and strong crystalline chains.
1.2.5 – CELLULOSE AS A RAW MATERIAL
Lignin and cellulose (lignocellulose) is one of the most
common substances on Earth used in paper making.
The wood pulp is treated with strong alkalis and
bisulfates to break the lignin. Cellulose is a major food
source for ruminants but not for humans, due to the
lack of enzymes needed for digestion. Cellulose is the
main component of paper, and could also be made
into cellophane and rayon. Cellulose can also be made
into plastics, with the dwindling supply of oil; cellulose
is a viable alternative as it is plentiful in plants. It consists of carbon and can be used as the starting molecule for
petrochemicals.
Cellulose is hard to break due to the hydrogen bonds in the long, near linear structure. Cellulose enzymes in
bacteria and certain fungi can be used to break cellulose; it can also be broken by using a sulfuric acid solution.
Yeast and bacterium fermentation can be used to convert glucose into ethanol, bacterium Zymomonas mobilis
can make the process more effective. Dehydrating ethanol in concentrated sulfuric acid or phosphoric acid can
produce ethylene. This process of converting cellulose to ethylene is feasible but unviable due to costs.
1.3 – OTHER RESOURCES, SUCH AS ETHANOL, ARE READILY AVAILABLE FROM RENEWABLE
RESOURCES SUCH AS PLANTS
1.3.1 – THE DEHYDRATION OF ETHANOL TO ETHYLENE
Dehydration is the removal of water from ethanol to create ethylene. The removal of a hydroxide group from
one end of ethanol and a hydrogen atom from the other end can form water and the resulting molecule is
ethylene.The overall chemical reaction for the dehydration of ethanol is: 𝐶𝐻3 𝐶𝐻2 𝐶𝐻 → 𝐶𝐻2 𝐶𝐻2 + 𝐻2 𝑂. Sulfuric
acid acts both as a dehydrating agent and as a catalyst.
1.3.2 – THE ADDITION OF WATER TO ETHYLENE
Hydration of ethylene is an example of addition reaction with alkenes, where the ethylene is then turned into
ethanol. Like the dehydration of ethanol, highly concentrated sulfuric acid is also used in the hydration process
to form a mixture of ethyl hydrogen sulfate and diethyl sulfate. Dilution of the mixture produces ethanol, but it
can generate a lot of environmental problems, however using a zeolite catalyst has reduced the problem.
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By: Raymond Chen
Chapter 1 – Production of Materials
1.3.3 – ETHANOL AS A SOLVENT
Alcohols derived from alkanes are known as alkanols. This is where one end of the molecules has a hydroxyl
group, -OH and at the remainder is a typical hydrocarbon chain, CH3CH2. The hydroxyl group makes ethanol
polar, with the H at the end slightly positive. The H can form weak hydrogen bonds with the slightly negative O
on the start of another ethanol molecule, thus increasing its boiling point and melting point. Hydrogen bonds
form between water, hence accounting for the high level of solubility. The hydrocarbon at the end of ethanol
allows it to be soluble in other hydrocarbons, such as hexane, and some natural oils too. The longer the
hydrocarbon chain the less soluble it is in water.
1.3.4 – ETHANOL AS A FUEL
Ethanol combusts is the presence of high temperatures and oxygen, producing a lot of energy. It can be burnt
cleanly and is easy and safe to transport, it is suitable for use in internal combustion engines – due to the
amount of energy released. The oxygen atom in ethanol leads to a cleaner burn with less soot formation. It is
renewable as it can be produced from plants.
1.3.5 – FERMENTATION OF SUGARS
Ethanol is mainly from sugar cane and corn. The fermentation process, yeast is used to convert sugars into
ethanol in the absence of oxygen. This way, yeast obtains energy from its environment. Commonly, most
industrial ethanol is produced from ethylene, while drinking ethanol is produced via fermentation. The process
involves:
1. Grind the grain, tubers or fruit with water.
2. -amylase, an enzyme to help break down the glucose-glucose molecules in starch is added to produce
maltose – at around 77C. the enzyme glucoamylase splits the disaccharide into glucose.
3. Yeast is added to convert glucose to carbon dioxide and ethanol. Year provides enzyme maltase (maltase
glucose) and zymase (glucose  ethanol). This is done in the absence of air and at 30-60C.
The aqueous mixture can be distilled to give 95% ethanol. Yeast produces ethanol as its waste product from
cellular respiration by which is extracts energy from its chemical environment. If the concentration is above 15%,
the yeast can be killed, therefore preventing further fermentation.
1.3.6 – THE MOLAR HEAT OF COMBUSTION OF ETHANOL
The molar heat of combustion of a compound is the amount of energy, in joules, released per mole. Incomplete
combustion occurs when oxygen is restricted and produces carbon monoxide or carbon (soot). Incomplete
combustion doesn’t release much heat and is wasteful of fuel. Molar heat of combustion for a fuel can be
determined experimentally by calorimetry.
Example:
78
Initial mass of burner + alcohol (g)
Final Temperature (C)
20
Final mass of burner + alcohol (g)
Initial Temperature (C)
58
Mass of alcohol used (g)
Temperature Difference (C)
Ie. 1.39 grams of ethanol raised the temperature by 58C
𝑛=
5
By: Raymond Chen
𝑚
1.39
→
= 0.0302 𝑚𝑜𝑙𝑒
𝑀
46.0 (𝑚𝑜𝑙𝑎𝑟 𝑤𝑒𝑖𝑔ℎ𝑡)
38.91
35.52
1.39
Chapter 1 – Production of Materials
∆𝐻 = 𝑚𝐶∆𝑡 → 4.184 × 150 (𝑎𝑚𝑜𝑢𝑛𝑡 𝑜𝑓 𝑤𝑎𝑡𝑒𝑟) × 58 = 36.4𝑘𝐽
36.4
= 1205 𝑘𝐽/𝑚𝑜𝑙
0.0302
1.3.7 – ADVANTAGES AND DISADVANTAGES OF ETHANOL FUEL
When compared to octane, ethanol is a bigger pollutant, 688.6kJ/mol to 683.5kJ/mol, respectively. Added with
the CO2 produced during fermentation, it is even worse. However, ethanol produces CO2 that has been
previously captured by plants, hence it is carbon neutral. Oxygen in ethanol ensures cleaner and complete
combustion. Burning petrol can form cancerous products including: carbon monoxide, soot and polyaromatic
hydrocarbons are produced; however additives are used to minimise the emissions, hence the presence of a
petrol-ethanol mix.
E10 is an alternative to petrol, where 10% of it is ethanol. It is a viable alternative both economically and
environmentally. Brazil currently adds ethanol (22% in some areas) to their petrol and vehicle engines are
modified to accommodate water. This has resulted in crops grown specifically for ethanol, as it is cheaper and is
an alternative and renewable source of energy.
Advantages
Renewable
Reduced carbon emissions
Cleaner combustion
Disadvantages
Requires a lot of land to produce the crops
High cost of distillation
Modifications of engines required to use ethanol
1.3.8 – NAMING ALKANOLS
Alkanols have a hydroxyl group, -OH which is the reactive part of the compound. The general formula for
alkanols is 𝐶𝑛 𝐻2𝑛+1 𝑂𝐻. They are names like alkanes and alkenes, with the number of carbon present and the
position of –OH hydroxyl group in the molecule.
1.4 – OXIDATION-REDUCTION REACTIONS ARE INCREASINGLY IMPORTANT AS A SOURCE OF
ENERGY
1.4.1 – DISPLACEMENT OF METALS FROM SOLUTION
In a displacement reaction:


The more reactive element changes from an element to an ion (from solid into solution)
o 𝐶𝑢 → 𝐶𝑢2+ + 2𝑒 − (more reactive therefore from solid into solution)
The less reactive element changes from an iron to an element (from solution to solid)
o 𝐴𝑔2+ + 2𝑒 − → 𝐴𝑔
The above reactions can be shown in a reaction equation:
1. 𝐶𝑢 → 𝐶𝑢2+ + 2𝑒 −
2. 𝐴𝑔+ + 𝑒 − → 𝐴𝑔
2+
2+
3. 𝐶𝑢(𝑠) + 2𝐴𝑔(𝑎𝑞)
→ 2𝐴𝑔(𝑠) + 𝐶𝑢(𝑎𝑞)
The oxidation half equation (Cu is the reductant)
The reduction half equation (Ag is the oxidant)
Overall reaction
Reactions of metals with dilute acids are different as the metal displaces the hydrogen ion from the solution.
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By: Raymond Chen
Chapter 1 – Production of Materials
Metallic tug-of-war, the more reactive metal prefers to be in solution and thus can force its valence electrons onto a
less reactive species.
1.4.2 – RELATIVE ACTIVITY OF METALS
The activity series is as follows:
K Na Ba Ca Mg Al Mn Zn Fe Ni Sn Pb (H) Cu Hg Ag Pt Au
 Decreasing reactivity 


Metals above calcium react with water and steam to produce hydrogen
Metals above lead react with acids to produce hydrogen
Reactions between acids and metals are exothermic – the more reactive the metal, the more heat released.
1.4.3 – OXIDISATION STATES
Oxidisation numbers show whether oxidisation or reduction has occurred in a reaction. They are assigned
Roman numerals. The rules include:
1.
2.
3.
4.
5.
6.
Oxidisation numbers of a compound in the elements are the charges of the ions: eg, Na+ is +1 and Cl – is -1.
The oxidisation number of an atom in an elementary substance is 0.
A neutral molecule has an oxidisation number of 0.
The algebraic sum of the oxidisation numbers is the charge on the ion: eg, CO32- is -2
Hydrogen generally has the oxidisation number of +1 but is -1 in a hydride.
The more electronegative substance will have the negative oxidisation number: eg, ClF, F is -1 while Cl is
+1 as F is more electronegative.
Oxidisation numbers indicate electron transfer in redox reactions: oxidation ↑ and reduction .
1.4.4 – GALVANIC CELLS
Galvanic cells are created by two half cells, a salt bridge and an external circuit. The more reactive metal (the
reductant, oxidised anode) is oxidised with the metal ion go into the solution and the electrons passing through
the external circuit. The electrons then reach the less reactive metal (the oxidant, reduced cathode) where it is
reduced with electrons forming the metal from the ions in the solution.
The salt bridge allows for the passage of electric current in the form of ions. Excess reductant ions enter the
salt bridge to move to the other side. The anions from the salt solution (nitrate) moves from the salt bridge into
the reductant’s solution. In the oxidant’s solution, the nitrate anions move into the salt bridge.
1.4.5 – REDOX REACTION IN GALVANIC CELLS
Anode is the negative terminal of the battery, where the more reactive oxidant electrode is placed. Cathode is
the positive terminal of the battery, where the more stable reductant electrode is placed. Electrolyte is the
liquid that the electrodes are placed in.
Oxidation takes place on the anode side as electrons are lost to the positive terminal where reduction takes
place, taking in the free electrons.
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By: Raymond Chen
Chapter 1 – Production of Materials
1.5 – NUCLEAR CHEMISTRY PROVIDES A RANGE OF MATERIALS
1.5.1 – RADIOACTIVITY
Most natural elements occur in several forms called isotopes. Isotopes are just a variation of the same element,
as are so due to the differing number of neutrons in the nucleus. However the isotopes don’t affect the physical
and chemical properties of the elements.
The stability of the isotopes is dependent on the makeup of the nucleus. Elements that have an unstable nucleus
undergo radioactive decay:



Alpha particles are the helium nuclei (2 protons + 2 neutrons): 42𝐻𝑒 ()
Beta particles are high speed electrons: −10𝑒 ()
Gamma radiation are high energy electromagnetic radiation ()
The stability of the nucleus depends on the neutron to proton ratio (n:p):


Light elements – (z<20) are stable if n:p ~ 1:1
Heavy elements – (z>80) are stable if n:p ~ 1.5:1
Radiation Cause of Instability
Mechanism
Alpha
Emission of 42𝐻𝑒
4
+2
𝑛 → 𝑝 + 𝑒−
1
1836
1
1836
-1
Beta
Too many protons and
neutrons
n:p ratio too high
Positron
n:p ratio too low
Gamma
Excess energy
Mass (H=1)
𝑛 → 𝑝 + 𝑒+
Charge
+1
Penetrating
Ability
Few centimetres
of air
Few millimetres
of aluminium
Few millimetres
of aluminium
Several cm of Pb
Nuclear equations are used to show what happens in nuclear decay.
Alpha decay – cadmium decays by emitting an alpha particle and changing into palladium:
114
48𝐶𝑑
→
110
46𝑃𝑑
+ 42𝐻𝑒
Beta decay – carbon-14 decays to nitrogen-14 and a beta particle:
14
6𝐶
→
14
7𝑁
+
0
−1𝑒
Gamma decay – when a neutron bombards bromine-79 it turns it into an excited bromine-80.
It can relieve the excess energy by emitting gamma radiation.
80
35𝐵𝑟
→
80
35𝐵𝑟
+ 𝛾
In each of the nuclear reactions:


The total electric charge (sum of atomic numbers) is the same on each side of the equation
The sum of the mass numbers is the same on each side of the equation.
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By: Raymond Chen
Chapter 1 – Production of Materials
1.5.2 – TRANSURANIC ELEMENTS
Transuranic elements have an atomic number larger than 92. They don’t exist naturally instead they are
produced by beta decay. The artificial creation of these elements has no practical use, but instead allows
scientists to learn about the structure of the nucleus.
A neutron bombards unranium-238 to form neptunium-239 which is largely unstable. As a result it undergoes
natural beta decay to form a more stable plutonium-239.
238
92𝑈
+ 10𝑛 →
239
93𝑁𝑝
239
92𝑈
→
→
239
94𝑃𝑢
239
93𝑁𝑝
+
+
0
−1𝑒
0
−1𝑒
Transuranic elements are created by bombarding elements with neutrons and more recently, they have been
created by accelerating nuclei of atoms using linear accelerators and cyclotrons and bombarding them into
heavy nuclei.
1.5.3 – PRODUCING COMMERCIAL RADIO ISOTOPES
Some naturally occurring isotopes are extracted from naturally occurring ores, but it is far more efficient for
them to be produced in a nuclear reactor or a cyclotron.
A nuclear reactor is a device containing sufficient fissionable material arranged so that a controlled chain
reaction may be started up and maintained in it. As nuclear reactors is neutron rich, isotopes are normally formed
via neutron bombardment. For example, cobalt-60, used for gamma radiation of cancers, can be made by
bombarding cobalt-59 with neutrons. Other isotopes produced like this include, iodine-131 and strontium-90.
Cyclotrons are an electromagnetic device that contains no uranium-bearing fuel elements. Positive particles are
accelerated by passing them through alternating positive and negative fields. A strong magnetic field is used to
keep the particles moving in a spiral path. When very high speeds are achieved, the positive particles are allowed
to collide with atoms of the target substance.
1.5.4 – DETECTING RADIATION
Radiation exposes photographic film even if that film is kept in the dark – thus radiation can be detected.
Workers who come into contact with radiation wear exposed pieces of photographic film which are developed
regularly to determine the level of exposure – the more darkening, the more exposure.
Cloud chambers can be used, as alpha, beta and gamma radiation leave ionising tracks. These tracks are visible in
the cloud chamber due to the presence of a supersaturated alcohol solution as a vapour.
The Geiger-Muller tube is a radiation counter.It can count individual particles at rates of up to 10 000 per second.
The radiation enters the GM tube through a mica window at one end. Inside the tube is a low-pressure inert gas
such as argon. The high-energy particles cause electrons to be ejected from the neutral atoms. A high voltage is
maintained between a copper cathode and a central anode. The ionisation releases electrons, which are
attracted to the anode. As the electrons accelerate due to the high voltage, they cause more ionisations of
gaseous atoms, leading to a cascade of electrons that arrive at the anode. An amplified electrical pulse is created
at the anode and is detected by the digital counter.The positive ions are attracted to the negative casing and
accept electrons to complete the circuit.
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By: Raymond Chen
Chapter 1 – Production of Materials
1.5.5 – USES OF RADIO ISOTOPES
Radioisotope
Field
Decays to
Emission Type
Production
Technetium-99m
Medicine
Ruthenium-99
Gamma (γ) Radiation
Molybdenum-99 – Undergoes beta decay
Carbon-14
Industry
Nitrogen-14
Beta (β) Radiation
It is produced in nature by a number of
reactions involving cosmic rays. In living
substances, cabon-14 is formed as it decays.
Use
Used as a liver-bile tracer to determine the
functioning of the bile duct. It is also used to
detect blood clots, to assess damage after
heart attacks and to detect brain tumours.
The half-life of a touch over 6 hours is
extremely suitable, as it provides enough time
for the radioisotope to reach the desired area
and be detected, but it also doesn’t last too
long so that it might have any side effects.
Used to determine the age of underground
water. In a similar fashion it is also used to
determine the age of any material containing
carbon up to about 50 000 years old.
The half-life of 5730 years is suitable as it
allows a rough estimate of the age of certain
objects to be ascertained.
Suitability of
Half-Life
DEVELOPING AND USING A BIOPOLYMER




Polyhydroxybutyrate (PHB) is a biopolymer produced by Alcaligenes Eutrophus bacteria during the
fermentation of renewable carbohydrate feed stocks.
It has the potential of replacing polypropylene for use in packaging, bottles, bags and wrapping film.
PHB is renewable, biodegradable and biocompatible but further development is required.
It is expensive to produce, brittle and can’t handle high impact.
BATTERIES
Voltage(v)
Anode
Cathode
Electrolyte
Cost &
Practicality
Effect on
Society
Environment
10
Leclanché Dry Cell
1.5
Zinc casing
𝑍𝑛(𝑠) → 𝑍𝑛2+ + 2𝑒 −
Manganese Oxide (MnO2)
2𝑀𝑛𝑂2(𝑠) + 2𝑁𝐻4+ + 2𝑒 −
→ 𝑀𝑛2 𝑂3(𝑠) + 𝐻2 𝑂(𝑙)
+ 2𝑁𝐻3
Aqueous ammonium chloride
Cheap, low energy density, voltage will
gradually fall as electrolyte is used, short shelflife, zinc casing may oxidise.
Low drain appliances, where low currents are
sufficient
Parts mildly acidic, but are non-toxic, hence no
damage
By: Raymond Chen
Silver Button Cell
1.6
Zinc
𝑍𝑛(𝑠) + 2𝑂𝐻 − → 𝑍𝑛(𝑂𝐻)2(𝑠) + 2𝑒 −
Graphite (carbon) + Silver Oxide Past
𝐴𝑔2 𝑂(𝑠) + 𝐻2 𝑂(𝑙) + 2𝑒 − → 2𝐴𝑔(𝑠) + 2𝑂𝐻 −
KOH paste + Zinc Hydroxide
Silver is expensive, hence so are the cells. They
are non-rechargeable. Recycled so that silver
can be recovered. Long shelf-life.
Use in watches, cameras application that
require a low but constant voltage
None, but the KOH is caustic and can cause
burns
Chapter 1 – Production of Materials
ANALYSING BENEFITS AND PROBLEMS ASSOCIATED WITH THE USE OF RADIOACTIVE
ISOTOPES IN IDENTIFIED INDUSTRIES AND MEDICINE
Radioisotopes have enabled the use of new and innovative techniques to monitor and remedy problems more
effectively and economically than before. Previously either there was no easy way to perform these operations
in industries and medicine, or they were invasive. While the other benefits are many, they need to be weighed
against potential problems that might arise.
Radiation is harmful to living things. It can result in simple tissue damage, affect cancers or cause genetic
damage leading to deformities in offspring. It is therefore important that steps be taken to minimise harm to
workers using these materials, and to any patient who might be the recipients of the radiation. Safety
regulations are in place for the safe storage and handling of radioisotopes and the conditions under which they
may be given to patients or used in the environment.
DESCRIBING RECENT DISCOVERIES OF ELEMENTS
Ununpentium (Uup), atomic number 115, was discovered in 2003 by a collaborative effort between scientists in
Russia. This superheavy element survived for 30-80 milliseconds before undergoing alpha decay, forming into an
isotope of atomic number 113. Ununtrium (Uut), atomic number 113, survived approximately ten times longer
than the ununpentium. After undergoing a series more of alpha decays, the ununpentium eventually formed a
long-living isotope of dubnium, atomic number 105.
243
95𝐴𝑚
11
By: Raymond Chen
+
48
20𝐶𝑎
→
291
115𝑈𝑢𝑝