STAGE 2 CHEMISTRY
ASSESSMENT TYPE 1: Investigations Folio
Issues Investigation - Student 2 Response
Magnesium Production in Spencer Gulf
Part A Article Analysis
Student Name:
Source Number:
1
Student response
research skills
information source
(correctly formatted
reference)
Perth Sunday Times, Aussie alloy under test 16/02/2003
relevant information
highlighted in
materials submitted
communication
description of
information
Article is about a new Magnesium alloy being developed and why
it is better than current Aluminium alloys
The uses of this alloy are mainly in the car industry
analysis
relevance
(the degree to which
the source addresses
the topic)
Compares using new Magnesium allow with traditional
possibility of bias
(evidence of a
prejudiced or partial
viewpoint that
influences
interpretation of the
material)
Very in favour of new Magnesium alloy which indicates a bias
credibility
(the trustworthiness,
i.e. credentials,
education,
experience, peer
review etc. of the
source)
Written for a highly regarded Sunday newspaper
other factors
(ease of access,
clarity of language
and presentation,
use of diagrams)
Short and easy to read
Page 1 of 6
Aluminium alloys
Outlines advantages of Magnesium alloy (lighter and stronger)
Analysis and
Evaluation
Has analysed the
article and linked it
to the use of
magnesium but
not to the issue.
The writer is very experienced
Lots of people have this opinion
No diagrams or pictures were used
Stage 2 Chemistry annotated response
Ref:A121059 (revised January 2013)
© SACE Board of South Australia 2013
Article Analysis
Student Name:
Source Number:
2
Student response
research skills
information source
(correctly formatted
reference)
The Advertiser, ‘Beware Toxic Dangers of Smelting’
11/03/2002
relevant information
highlighted in
materials submitted
communication
description of
information
This is a letter to the editor and gives really good reasons why
the Magnesium smelter should not be located in Pt Pirie
analysis
relevance
(the degree to which
the source addresses
the topic)
Very good for negatives of the investigation
possibility of bias
(evidence of a
prejudiced or partial
viewpoint that
influences
interpretation of the
material)
The article is very bias
credibility
(the trustworthiness,
i.e. credentials,
education,
experience, peer
review etc. of the
source)
The Advertiser is a well-known and well respected newspaper
other factors
(ease of access,
clarity of language
and presentation,
use of diagrams)
Very easy to access
Page 2 of 6
Most of the articles were strongly favoured of the Magnesium
smelter
Article did not contain any positives about the smelter
Author belongs to a Conservation group who always oppose this
sort of development
One person’s opinion and so is not credible
Very short and easy to read letter
The language was very clear
No diagrams were used
Stage 2 Chemistry annotated response
Ref:A121059 (revised January 2013)
© SACE Board of South Australia 2013
Magnesium Production in Spencer Gulf
I have chosen to investigate Magnesium and it’s possible production in Spencer Gulf. It is
a very light metal and it is non-toxic, non-magnetic and is very strong. This is why it is
very useful in manufacturing. But Magnesium has advantages and disadvantages and
that is why the production of Magnesium in Spencer Gulf is an important issue.
As well as being very light, Magnesium is also very reactive and so, unlike Gold and
Silver, Magnesium is always found as a compound in nature.. This compound is called
magnesite and is very hard to produce.
There are two main ways of producing Magnesium for it’s ore. Firstly the silicothermic
process. This produces magnesium oxide in a molten slag at temperatures of 1200ºC1600ºC under low pressure to produce a Magnesium vapour. The Magnesium vapour is
then condensed. This can produce very pure Magnesium.
Investigation
Subject outline
specifies that
students formulate
a question. This
allows opportunity
for evidence to
reflect the ‘A’
standard.
A possible
question for this
investigation could
be “Should
magnesium be
produced in
Spencer Gulf?”
The molten magnesium has to be protected from the air because it will react with oxygen.
This can be done using sulphur dioxide but it can be a health hazard as it’s bad for the
respitory system. Also it can cause acid rain. More recently it has been done with sulphur
hexafluoride.
The equation for this is
Si(s) + MgO(s) → SiO2(s) + Mg(g)
The second process is more common. Magnesium is produced by electrolysis. Molten
magnesium chloride is electrolyzed at 700 ºC. This process produces Magnesium that is
not as pure as the other process. The Australian Magnesium Process is a process that
was developed in Australia. It involves dissolving pure magnesite ore in hydrochloric acid
to produce magnesium chloride. The magnesium chloride is then purified. It is then
dehydrated and put into an electrolytic cell. You have to use electrolysis because
Magnesium is very reactive and so needs a lot of energy to produce it. Chlorine gas
released is at the other electrode and is then recycled and combined with hydrogen, from
natural gas to produce HCl and this can be used again. The Magnesium is produced at
the cathode by a reduction reaction and chlorine is produced at the anode.
Application
Generally uses
appropriate
chemical terms,
and conventions.
Equations are
mostly correct.
The half equation for the electrolysis reactions are
Mg2+ + 2e  Mg
2Cl-  Cl2 + 2e
Page 3 of 6
Stage 2 Chemistry annotated response
Ref:A121059 (revised January 2013)
© SACE Board of South Australia 2013
Different people have different opinions about whether Pt. Pirie should have a
smelter. The map shows the Spencer Gulf and Pt. Pirie.
The map provided here has been removed from the exemplar for copyright reasons.
The magnesium ore mine is close to Pt Pirie and so it’s easy to get the ore to Pt
Pirie (eg, by train or truck). Also, a new green power station would be built near Pt
Pirie to provide the energy. This would also mean that there will be more jobs in
the mine and the power station, so leading to more employment in the town.
However, there are also some problems as well. Toxic emissions from the
electrolysis can get into the air, food and water and there are concerns that some
of the chemicals in the water-cooling unit could get into the gulf and cause water
pollution. Dioxins and furans and POP’s cause air pollution and these can cause
cancer and suppress the immune system. If sulfur hexaflouride is used it is a
greenhouse gas and so it absorbs the sun’s heat and keeps it in the atmosphere
and so contributes to global warming if it leaks out. This would cause the sea
levels to rise and, as Pt. Pirie is on the coast, this could cause problems for
housing and businesses.
One way of solving this problem would be to monitor the air, soil and water around
the plant to detect any contamination. This could provide more employment. Or
you could have a buffer zone around the plant to prevent air pollution from
effecting local residents. One of the things that has been concerning Pt Pirie is the
lead from other industries getting in the soil and effecting children and this wouldn’t
produce any lead so that it would be a better industry for the town.
Analysis and
Evaluation
Appropriate but
superficial
connections made
between
information,
concepts and
perspectives.
Knowledge and
Understanding
Chemical basis of
perspectives
recognised with
explanations
provided.
Application
Simple
solutions to
problems
suggested.
Conclusion
In my opinion, magnesium is a very valuable metal because of the many different ways in
which it can be used. Setting up a production plant in a place such as Pt Pirie would have
advantages and disadvantages. Economically it would be very good for the area because
it would enable many more people to gain employment and take advantage of the mining
boom. It would also be good economically for Australia because the Magnesium could be
exported to other countries.. Also it could replace other industries that are causing
concerns at the moment, like lead. On the other hand it also causes a lot of pollution.
Page 4 of 6
Analysis and
Evaluation
Information used
to take a personal
stance but the
justification is a
repetition of points
made earlier.
Stage 2 Chemistry annotated response
Ref:A121059 (revised January 2013)
© SACE Board of South Australia 2013
References
Perth Sunday Times, Aussie alloy under test 16/02/2003
The Advertiser, ‘Beware Toxic Dangers of Smelting’ 11/03/2002
http://www.australianminesatlas.gov.au/education/fact_sheets/magnesium.jsp
This website is provided by the Australian Government through Geoscience Australia so it
is a credible site and isn’t bias. It is a fact sheet that tells me almost everything I need to
know about magnesium production in Australia.
http://mg.tripod.com/mggen.htm
This site explains about magnesium production and refining.
http://en.wikipedia.org/wiki/Pidgeon_process
This gives details and reactions for the process of magnesium production.
Word count: Evaluations - 191
Report - 767
Total: 958
Additional Comments
A range of sources selected. Sources are mostly relevant but limited in scope and suitability. Acknowledgement of
sources is generally clear but incomplete or incorrect. (Investigation)
Page 5 of 6
Stage 2 Chemistry annotated response
Ref:A121059 (revised January 2013)
© SACE Board of South Australia 2013
Performance Standards for Stage 2 Chemistry
A
Investigation
Analysis and
Evaluation
Application
Knowledge and
Understanding
Designs logical, coherent, and detailed plans for
chemistry investigations.
Critically and systematically
analyses data and their
connections with concepts to
formulate logical and
perceptive conclusions and
make relevant predictions.
Applies chemistry concepts
and evidence from
investigations to suggest
solutions to complex
problems in new and familiar
contexts.
Consistently demonstrates a
deep and broad knowledge
and understanding of a range
of chemistry concepts.
Critically and logically
evaluates procedures and
suggests a range of
appropriate improvements.
Uses appropriate chemical
terms, conventions, formulae,
and equations highly
effectively.
Critically and logically selects and consistently
and appropriately acknowledges information
about chemistry and issues in chemistry from a
range of sources.
Manipulates apparatus and technological tools
carefully and highly effectively to implement wellorganised safe and ethical investigation
procedures.
Demonstrates initiative in
applying constructive and
focused individual and
collaborative work skills.
Obtains, records, and displays findings of
investigations using appropriate conventions and
formats accurately and highly effectively.
B
Designs well-considered and clear plans for
chemistry investigations.
Logically selects and appropriately acknowledges
information about chemistry and issues in
chemistry from different sources.
Manipulates apparatus and technological tools
carefully and mostly effectively to implement
organised safe and ethical investigation
procedures.
Clearly and logically analyses
data and their connections
with concepts to formulate
consistent conclusions and
make mostly relevant
predictions.
Logically evaluates
procedures and suggests
some appropriate
improvements.
Designs considered and generally clear plans for
chemistry investigations.
Selects with some focus, and mostly
appropriately acknowledges, information about
chemistry and issues in chemistry from different
sources.
Manipulates apparatus and technological tools
generally carefully and effectively to implement
safe and ethical investigation procedures.
Prepares the outline of one or more chemistry
investigations.
Selects and may partly acknowledge one or more
sources of information about chemistry or an
issue in chemistry.
Uses apparatus and technological tools with
inconsistent care and effectiveness and attempts
to implement safe and ethical investigation
procedures.
Identifies a simple procedure for a chemistry
investigation.
Identifies a source of information about chemistry
or an issue in chemistry.
Attempts to use apparatus and technological
tools with limited effectiveness or attention to safe
or ethical investigation procedures.
Attempts to record and display some descriptive
information about an investigation, with limited
accuracy or effectiveness.
Page 6 of 6
Uses knowledge of chemistry
logically to understand and
explain social or
environmental issues.
Analyses data and their
connections with concepts to
formulate generally
appropriate conclusions and
make simple predictions with
some relevance.
Applies chemistry concepts
and evidence from
investigations to suggest
some solutions to basic
problems in new or familiar
contexts.
Demonstrates knowledge and
understanding of a general
range of chemistry concepts.
Evaluates some procedures
in chemistry and suggests
some improvements that are
generally appropriate.
Uses generally appropriate
chemical terms, conventions,
formulae, and equations with
some general effectiveness.
Applies generally
constructive individual and
collaborative work skills.
Describes basic connections
between some data and
concepts and attempts to
formulate a conclusion and
make a simple prediction that
may be relevant.
For some procedures,
identifies improvements that
may be made.
Applies some evidence to
describe some basic
problems and identify one or
more simple solutions, in
familiar contexts.
Attempts to use some
chemical terms, conventions,
formulae, and equations that
may be appropriate.
Attempts individual work
inconsistently, and
contributes superficially to
aspects of collaborative work.
Obtains, records, and displays findings of
investigations using conventions and formats
inconsistently, with occasional accuracy and
effectiveness.
E
Demonstrates some depth
and breadth of knowledge and
understanding of a range of
chemistry concepts.
Uses a variety of formats to
communicate knowledge and
understanding of chemistry
coherently and effectively.
Obtains, records, and displays findings of
investigations using generally appropriate
conventions and formats with some errors but
generally accurately and effectively.
D
Uses appropriate chemical
terms, conventions, formulae,
and equations effectively.
Uses a variety of formats to
communicate knowledge and
understanding of chemistry
coherently and highly
effectively.
Applies mostly constructive
and focused individual and
collaborative work skills.
Obtains, records, and displays findings of
investigations using appropriate conventions and
formats mostly accurately and effectively.
C
Applies chemistry concepts
and evidence from
investigations to suggest
solutions to problems in new
and familiar contexts.
Uses knowledge of chemistry
perceptively and logically to
understand and explain social
or environmental issues.
Attempts to connect data with
concepts, formulate a
conclusion and make a
prediction.
Acknowledges the need for
improvements in one or more
procedures.
Uses knowledge of chemistry
with some logic to understand
and explain one or more
social or environmental
issues.
Uses different formats to
communicate knowledge and
understanding of chemistry
with some general
effectiveness.
Demonstrates some basic
knowledge and partial
understanding of chemistry
concepts.
Identifies and explains some
chemistry information that is
relevant to one or more social
or environmental issues.
Communicates basic
information to others using
one or more formats.
Identifies a basic problem
and attempts to identify a
solution in a familiar context.
Demonstrates some limited
recognition and awareness of
chemistry concepts.
Identifies some chemical
terms or formulae.
Shows an emerging
understanding that some
chemistry information is
relevant to social or
environmental issues.
Shows emerging skills in
individual and collaborative
work.
Attempts to communicate
information about chemistry.
Stage 2 Chemistry annotated response
Ref:A121059 (revised January 2013)
© SACE Board of South Australia 2013