The forensic science option of the chemistry syllabus is, as the name indicates, taught in the context of forensic science. This context does not only include investigating murders but a range of things including evolution patterns and tracing the origins of chemicals.
It teaches students that the shapes compositions and behaviours of chemicals are useful tools in solving problems in all sectors in our society. It also teaches students that forensic chemists work in the general field of analytical chemistry and that these scientist analyse compounds and mixtures to identify trends or patterns in evidence and draw conclusions from a wide range of investigations.
We suggest the topic be taught using three prescribed focus areas. Theses are:
The topic is to be taught in 30 indicative hours for which we have broken the topic up into individual lessons. These are a guide only as the length of time spent on each point will depend on their prior knowledge and understanding. As much of the content does not connect very closely to the core the students may need a substantial amount of time on the basics of organic chemistry. Students how are also studying biology will probably understand the content faster than those that have not.
The topic consists of seven main dot points. The first one is:
The content to be taught for this dot point is the importance of contamination and a general introduction to organic chemistry and the role of the forensic chemist.
The second dot point is:
This point teaches students about carbohydrates, specifically monomers, polysaccharides, reducing and non-reducing sugars. Students also learn the differences between cellulose, starch, glucose, and glycogen.
The third dot point is:
This teaches the general formula of fats , the physical and chemical properties of fats and some of the differences in between lipids that are produced and stored by different organisms.
The forth dot point is:
Included in this point is the difference between structural and enzymatic proteins, that proteins are chains of amino acids joined by peptide bonds, the general formula of amino acids, and the role of chromatography and electrophoresis is separating and identifying proteins.
The fifth dot point is:
Students learn about the structure and composition of DNA and how DNA allows identification of individuals.
The sixth dot point is:
The content to be taught in this section includes testing methods that are both destructive and non destructive and the consequences of using these different methods for an investigation. Of the different methods looked at the following must be included: electron spectroscopy, atomic force microscopy, scanning tunnelling microscopy and spectrometers.
The seventh dot point is:
Students learn the conditions for atoms to emit light, that atoms emit certain wavelengths of light and why and that the light emitted can be within the wavelengths detectable as colour as well as in the infra-red and ultra-violet wavelengths. They are also taught about equipment that can be used to identify elements using the unique absorption spectra of those wavelengths.
The skills that the students need and develop through the topic are working aseptically to avoid contamination, writing up practical reports, researching from secondary sources and problem solving.
Throughout the topic there are a range of activities for the student to do to test and further develop the skills just mentioned. A large number of the activities are first hand investigations. These can be used to develop the students skills in writing practical reports and working aseptically. Included in the first hand investigations are a number of molecular modelling activities that can be either by molecular model kits or through the use of computer simulations.
Other activities require the students to work in a problem solving manner. These problem solving activities are re-occurring and require the students to investigate and device a solution to one or more real or mock cases just as a forensic scientist would do.
Another major activity that the students are required to do is to investigate a tool or method used by forensic scientists to analysis very small samples. This investigation covers the content in dot point six. It is presented as an assignment in which each student has to present a tool as if they were presenting to forensic scientists and they have to sell their product to them.
In order for the students to do all of the activities that have been outline the school needs to have access to molecular model kits and/or computer simulations. Apart from the actual resources it is also important to have some good references. For this reason we have included a comprehensive but not exhaustive list of references. While our list is good it is a good idea to keep relevant newspaper articles to use in class as case studies the more recent a case the more interesting it is likely to be for the students. It is also important as teaching the topic using a case-based approach is the easiest way to keep the topic in context.
Problems that teachers may come across when trying to teach this topic include access to equipment. The syllabus requires students to perform a first hand investigation with electrophoresis. The equipment required to do this may be difficult to find in schools. The topic also requires students to make molecular models of carbohydrates, lipids, proteins, and DNA. This means there needs to be a large number of molecular model kits for such large molecules to be made. Instead of using the molecular model kits there is also the option of using a computer simulation. This also has problems through as not a lot of schools would have such software and may not have the buget to go and buy it as they already have to buy some new equipment in order to teach the core of the new syllabus.
Another problem is that a lot of the content taught in the option is completely new. This is a problem because to get through all of the information it is important for the students to have a basic background in organic chemistry. The core however covers only a very small amount of information on organic chemistry in comparison.
The content of this topic has a very strong slant towards biology. While this will not be a problem for all teachers, for those that have not taught biology for a while may find it very difficult to teach and may resent teaching it.
As with all of the topics throughout the syllabus it is new and information at the correct level can be difficult to find. This is especially true for information on things like atomic force microscopy and how to use a spectroscope. The
theory behind how it works is easily found. A large reason for this is that there as yet no textbooks. This should be fixed in time.
While this option is not as large as others it is still big and will take a long time as the students do not have enough background in organic chemistry through the core of the syllabus as needed. The option also requires students to do a lot of first hand demonstrations and while that in itself is not a bad thing it does mean that it will take a lot of time. Like much of biochemistry there is a lot of rote learning that needs to be done by the students to get through this topic.
One of the conceptional challenges that the students face through out this topic is the understanding of emission verses absorption spectrums. They need to understand that they are different and how they are measured.
Finally there is a problem keeping the whole thing in context and getting through to the students that forensic chemistry is not just looking at murder and finding a killer. We suggest this be done through case studies but this can be a problem if appropriate cases can't be found.
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1. (D) |
Students should be able to: ·Recall and explain keywords (evidence, accuracy, contamination) ·Appreciate the role of the forensic chemist ·Discuss the ethics of using forensic evidence
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H4 H12 H16 |
·The role of the forensic chemist, particularly highlighting the varied role rather than purely an interest in crime ·Development of importance of forensic analysis (historical) |
9.4.1 9.4.5 |
Video Watch a short segment from "Turner and Hooch", looking for as many forms of evidence as possible. Class brainstorming What constitutes evidence? What could be the role of a forensic chemist? Case Comparison Examine cases, both recent and historical, and look for the role of forensic evidence and the forensic chemist. |
Video: Turner and Hooch Newspaper clippings of cases (e.g. OJ Simpson, Azaria Chamberlain, Weewaa) |
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1.
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Students should be able to: · Identify that carbohydrates are composed of C, H, and O. · Identify the basic formula of a carbohydrate as Cn(H2O)n. · Describe using examples of a monosaccharide, disaccharide and polysaccharides. |
H6 H9
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Students learn: -recall organic molecules and basic chemistry -unique nature of the carbon atom and its ability to bond with many molecules -carbohydrates are found in living systems and used for structure and support and as an energy source. |
8.5.2 8.5.3 8.4.3
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Lecturette Organic chemistry introduction. Abundance of C-compounds. Cyclic ring structure (5 or 6 C). Matching Game Students must find their matching "partner" according to card with function, structure or other clue.
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Crowther and Freemantle(1991)
Wright, et al (1992)
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2.
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· Identify glucose as a monomer and describe condensation reactions leading to formation of sucrose, glycogen, starch and cellulose |
H6
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-Monomers combine to form compound sugars in a condensation reaction. A water molecule is released. -to describe the reaction in structural terms.
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9.2.2
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Model Making Using cardboard templates to produce monosaccharides, disaccharides and polysaccharides. Worksheet - Simple condensation reactions and formation of maltose and sucrose. Molecular model Kits Each group responsible for making a model of one of the following:- monosaccharide, starch, cellulose and glycogen Questions to answer Homework exercis |
Wright et al (1992) for worksheet template. |
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3. |
· Describe the chemical difference between reducing and non-reducing sugars.
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H11
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-Reducing sugars can be detected by using a reagent such as Benedicts or Fehlings. A positive test indicates the presence of a sugar with a free aldehyde group. -Presence of starch can be detected by using iodine.
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9.2.3 9.2.4
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Practical Testing of substances to determine if reducing or non-reducing sugars are present.
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Borgford and Summerlin(1988) "Bananas- the riper they are, the sweeter they are". p.251.
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4. |
· Distinguish between plant and animal carbohydrate composition · Describe the structure and function of cellulose, starch and glycogen. · Identify and describe other carbohydrate compounds produced by organisms other than a plant or mammal. · Discuss ways in which this information would be useful to forensic chemists
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H13 H14
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-Plants are a source of carbohydrate. Cellulose(cotton, linen, paper) used for structural support. Starch used for storage of energy. - Animals contain glycogen for storage of glucose. -Differences in the orientation of bond between glucose molecule that gives the CHO molecule its function. - to compare the structure of chitin with other molecules The main component of exoskeleton of insects, crustaceans, some fungi cell walls.
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9.2.2
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Workstations Examples of carbohydrates at each workstation, along with structural models to distinguish between plant and animal carbohydrates.
Library research -using internet, books to investigate a carbohydrate molecule. Students are to collect information on structure, use, function to present to class. They must make a 3-D model of their molecule.
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3
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Students should be able to:- Identify that fats are alkanoic acids with the general formula CH3(CH2)nCOOH
Identify that part of the fatty acid molecule which should mix with water
Identify glycerol as a triol and compare its reaction in cold KMnO4 with that of 1, 2 propandiol and 1-propanol
Discuss the differences in lipids produced and stored in organisms and explain how this may be used as an identifying feature by a forensic chemist. |
H6 : explains reactions between elements and compounds in terms of atomic structures and periodicity.
H6 : explains reactions between elements and compounds in terms of atomic structures and periodicity
H9 : describes and predicts reactions involving carbon compounds
H9 : describes and predicts reactions involving carbon compounds H11 : justifies the appropriateness of a particular investigation plan |
·Introduce the topic of lipids. ·Students to discuss what they know about lipids ·Sts to write down general info regarding lipids. ·T to give the general formula for lipids ·Lipids made up of glycerol and fatty acids ·Saturated ·Unsaturated
·Explain that phospholipids are amphipathic · hydrophilic · hydrophobic · Structure contains a phosphate group. · Discuss biological significance i.e. membrane structure
· Students to identify that glycerol is a 3-carbon alcohol which contains 3 hydroxyl (-OH) groups. · All of which can condense with a fatty acid to form an ester.
· Properties and functions of triglycerides · Function of lipids is energy stores in animals · Plants store oils · Fats are oxidised : metabolic water is a product e.g. kangaroo rat · Function of lipids other than fats and oils · Waxes · Phospholipids · Steroids · Terpens · Lipoproteins · gylcoproteins |
5.7.3a 5.7.3b 5.7.3d 8.2.1
8.2.1
8.2.1
5.7.3b
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·Brainstorm the new topic and conduct a general discussion on what they know about lipids. ·Worksheet outlining the general formula and other info : glycerol, Fatty Acid (FA), saturated and unsaturated. ·Activity using the molecular model kits.
·Teacher prepared worksheet outlining information on · phospholipids diagrams that illustrate the hydrophobic and hydrophilic parts. ·Structure of a phospholipid with a phosphate group. ·Discuss the biological significance i.e. membrane structures.
· Practical · Compare glycerol's reaction in cold dilute KMnO4 with that of 1, 2 propandiol and propanol. · Perform a first hand investigation to carry out distinguishing tests and gather first-hand information to identify: · fatty acids · glycerol
· Discussion of the different types of lipids how are they produced and stored. · From the book Biological Science 1 & 2 pg. 142 table 5.8 construct a worksheet that looks at the function of lipids other than fats and oils. |
Foundation Biology p40
Foundation Biology Pg. 40-41 Biology, Fifth Edition Pg. 57
Topics in Senior Chemistry Pg. 62-69
Biological Sciences 1 & 2. Pg. 142, 55-56 Foundation Biology Pg. 40 |
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1.
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Students to be able to: · Distinguish between structural and enzymatic proteins. · identify proteins using a test.
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H9: Describes and predicts reactions involving carbon compounds.
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Students learn: · Examples of proteins and where they are found (ie what animal/plant/ food). · Using those examples students learn to distinguish between structural and enzymatic proteins.
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· Students fill in a table using protein examples given to them by the teacher. The table would have the headings name of protein, where it is found, and the use. This can be done as a 1. Copy from the board exercise. 2. Group discussion exercise. 3. Rotational exercise where information is at each bench and students fill in the table by moving around the benches. · Students perform a test for protein using foods such as milk and egg and gelatine |
Green, N.P.O., Stout, G.W., and Taylor,D.J., 1990. Biological Sciences 1 & 2. 1984. ILPAC Unit 4 Independent Learning Project for Advanced Chemistry: Big Molecules.
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2 |
Students to be able to: · Define proteins as polymers of amino acids. · identify and draw amino acid function groups. · Describe the nature of the peptide bond. · Give an example of an enzyme that is able to break these bonds. · Explain how the enzyme breaks the bond with reference to the importance of it for forensic scientists |
H6: Explains relationship between elements and compounds in terms of atomic structure and periodicity. H9: Describes and predicts reactions involving carbon compounds. |
Students learn: · Proteins are a polymer of amino acids · What the functional groups of amino acids are. · How the amino acids bond (ie the peptide bond). · About one enzyme that can break the peptide bond of a protein and how this is done. |
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· Students: 1. Write the definition of protein. 2. Are given a handout with the definition on it. · Students 1. Draw a diagram of the general structure of an amino acid 2. Label one that is on a handout. · Fill in a cloze passage that describes a peptide bond and gives an example of an enzyme that can break the bond and how it does it all in the context of a forensic scientist trying to identify the protein type. · Do a first hand investigation by 1. Making a molecular model of an amino acid and protein. 2. Use computer simulation. · Teacher demonstration of electrophoresis and students answer questions on the process and how it works
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Green, N.P.O., Stout, G.W., and Taylor,D.J., 1990. Biological Sciences 1 & 2. Purves, W.K., Orians, G.H., and Heller, H. C., 1995. Life The Science of Biology (4th ed.). Stryer, L., 1995. Biochemistry (4th ed.). Tobin, A.J., and Morel, R.E., 1997. Asking About Cells. Tobin, A.J., and Pusheck, J., 1998. Asking About Life.
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3 |
Students to be able to: · Compare the process of electrophoresis and chromatography. · Identify the properties of mixtures that allow separation for both of the processes. · Justify why they would use either chromatography or electrophoresis over the other for a given mixture. |
H3: Assesses the impact and implications of research in chemistry on the development of technologies. H11: Justifies the appropriateness of a particular investigation plan. H12: Evaluates ways in which accuracy and reliability could be improved in investigations.
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Students learn: · What electrophoresis and how it works (ie what properties it separates). · What chromatography is and how it works (ie what properties it separates).
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· Do a first hand investigation of chromatography 1. Plant pigments on gel. Using different solvents. 2. Amino acid standards and an unknown mixture of amino acids on paper. · Students are given a case in which they have to separate some substances using either electrophoresis or chromatography. They have to write an investigation plan that details what procedure they are going to use and why in preparation of a criminal trial. |
1984. ILPAC Unit 4 Independent Learning Project for Advanced Chemistry: Big Molecules. 1977. Biological Science : The Web of Life. Teacher's guide Part 2. 1983. Biological Science : The Web of Life. Student's manual Part 2. Purves, W.K., Orians, G.H., and Heller, H. C., 1995. Life The Science of Biology (4th ed.). Stryer, L., 1995. Biochemistry (4th ed.). Tobin, A.J., and Morel, R.E., 1997. Asking About Cells. |
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1.(S) |
Students should be able to: · Outline structure and composition of DNA |
H13 |
· DNA structure - double helix of nucleotide sub- units - complementry base pairing and composition - nucleotides consist of a base, a pentose sugar and a phosphate group |
8.2.3 8.2.4 8.2.5 8.4.2 8.5.2 9.2.1 |
Video Review structure and function : video clip "Jurassic Park" with accompanying fill in the gaps worksheet Story Tell story of race to discover the structure of DNA 3D model From assorted materials (eg cardboard, pipe cleaners, blue tac etc) a 3D model is constructed. An accompanying sheet is designed to clarify the key used (eg pink cardboard is an adenine base, blue tac represents a hydrogen bond) |
· Video : Jurassic Park · Worksheet : with summary of structure and composition with fill in the gaps and labelling a diagram · Berry, A. Eureka and other stories. · Modelling materials |
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2.(D)
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· explain why analysis of DNA allows identification of individuals · describe processes used to analyse DNA, and their use in identifying individuals or identifying relationships between people |
H3 H4
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· methods of DNA analysis e.g. - electrophoresis - DNA fingerprinting - Polymerase chain reaction (PCR) · uses of these methods
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Lecturette Link to proteins and their methods of analysis e.g. electrophoresis Expert rotation In groups of 3 students read about, summarise and discuss one method of analysis and its usefulness -:using resources provided. Students rotate and explain the method to another 2 students, who reciprocally share their knowledge. Homework Consider the idea of DNA banks. Do you think they are ethical? |
-In the expert rotation it would b good to relate the method of analysis to a real case. Eg Kurland, M. How to solve a murder.
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3.(S)
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· Discuss ethics of keeping DNA banks and using DNA analyis as evidence
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H4 H16
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Ethical debate on use of DNA technology in evidence
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Debate Split class into 2 groups on basis of homework thought. Give both sides the same articles to read on the recent Australian case of the town of Wee Waa. Each side can brainstorm for further reasons to support their case. Debate is then held between 2 sides. Ethical writing Having had a chance to hear fresh viewpoints, students write a page on the ethics of DNA banks, DNA evidence.
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Newspaper article on Wee Waa (DNA fingerprinting) case
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1.(D) |
Students should be able to: · Identify, outline and assess the value of the following techniques; - Electron spectroscopy - Atomic-force microscopy - Scanning tunneling microscopy - Mass spectrometry · Explain what is meant by the destructive testing of material and explain why this may be a problem in forensic investigations |
H3 H11 H12 H13 H14 |
· Methods of operation, and benefits of, various techniques useful in analytical chemistry · Destructive testing : what it is and impact on forensic chemistry |
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Presentations These lessons are the culmination of a group project in which students have performed independent research on a specific technique. In these lessons the groups present their findings to the class. |
- It would be useful for students to contact companies directly to gather relevant information (either by internet or telephone) - A number of web sites provide details on these techniques : see reference list for useful starting sites |
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2 (D) |
¥ Recall ijmorganic and organic compounds ¥ Distinguish between organic and inorganic compounds ¥ Explain why the inorganic chemical properties of soils may be useful evidence |
H9 |
¥ Distinguish between organic and inorganic compounds |
9.4.5 |
Class case: Introducing the class case - A framework in which mini cases can be set through the unit. Makes it more interesting by maintaining the forensic context whilst learning basic organic chemistry Experiment Organic v Inorganic compounds |
Deretic, G and Ware G (1995). Senior Chemistry Manual, Melbourbe: Heinemenan |
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3 (S) |
¥ Explain that there are different classes of carbon compounds ¥ Recognise that these compounds can be identified by distinguishing tests |
H6 H9 |
¥ Different carbon classes (hydrocarbons, alkanoils, alkanoic acids) ¥ Properties, both physical and chemical, of these compounds ¥ Structure and bonding of these compounds ¥ Distinguishing tests |
8.2.3 8.2.4 8.2.5 8.4.2 8.5.2 9.2.1 |
Assignment Introduction to the assignment, with a letter given to each group allocating the task and setting our requirements. Details in dot point six Circus Information and demonstrations at stations. Questions to be answered and table to be constructed by students to summarise information |
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1.
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Students should be able to:- ® Describe conditions under which atoms will emit light. ® Identify that emission of quanta of energy may be detected by humans by a specific colour. ® Explain why excited atoms in gas phase emit or absorb a certain wavelength of light ® Explain that each element produces a unique line emission spectrum |
H 3 H 4 H 6
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Students learn:- · Atoms give off energy in form of radiation when exposed to high energy. · The emitted light may be a continuous or a discrete spectra · To identify examples in the everyday world. E.g. Street lamps, fireworks. · Every atom has its own characteristic spectrum which can be used for its detection. |
8.2.3 8.3.2
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Lecturette Revise prior knowledge and theory : atomic structure, electron shells, electromagnetic spectrum and wavelengths of visible light. Worksheet Close passage to be completed which will test knowledge. Case study Used to motivate and link the necessity of trace element analysis as a useful tool for the forensic chemist |
Basic chemistry or physics text for background theory. E.g. Halliday, et al, 1993.
Evans (1996) and Fisher (1995) have a wide range of suitable case studies for trace element analysis. |
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2. |
· Discuss the use of line emission spectra to identify the presence of elements in chemicals.
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H3, H 4 H11, H12 H13, H14 H16
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· Identify data, choose equipment and investigate the emission spectrum of elements by use of flame tests. · History of the development of the spectroscope by Robert Bunsen. · The use of a spectroscope and its value for the forensic chemist to identify components in an unknown mixture. |
9.4.3
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Flame test practical - identify metal elements by flame tests -using a spectroscope and gas discharge tubes Problem solving exercises to analyse and identify individual elements in a mixed emission spectrum |
Deretic and Ware, 1995
Thickett, 1996.
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3. |
® Describe other methods of analysis such as infra-red and ultra-violet spectroscopy. ® Discuss the advantages and disadvantages of these methods and their use in identifying elements
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H3, H4 H12, H16
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· The difference between absorption and emission spectra. · The principle behind the operation of these instruments · Use of new technology allows for better analysis and detection. · The value of non-destructive methods for analysis. |
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Lecturette - the difference between emission and absorption spectra. Visiting Speaker -invite a forensic chemist to visit class. -students to prepare questions to ask the speaker as assignment. -an excursion to forensic chemistry laboratory could alternatively be arranged. |
Chemistry in Britain 11, 434-451.
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Carbohydrates
Reducing sugars. The reducing sugars include all monosaccharides, such as glucose and fructose, and some disaccarides, such as maltose. Use 0.1-1% sugar solutions.
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Test |
Observation |
Basis of test |
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Benedict's test Add 2mL of a solution of the reducing sugar to a test-tube. Add an equal volume of Benedict's solution. Shake and bring gently to the boil, shaking continuously to minimise spitting.
Fehling's test Add 2ml of a solution of the reducing sugar to a teat-tube. Add 1 mL of Fehling's solution A and 1mL of Fehling's solution B. Shake and bring to the boil. |
The initial blue colouration of the mixture turns green, then yellowish and may finally form a brick-red colour.
The initial blue colouration of the mixture turns green to yellow and finally a brick-red precipitate is formed. |
Benedict's solution contains copper sulfate. Reducing sugars reduce soluble blue copper sulfate, containing copper (11) ions (Cu2+) to insoluble red-brown copper oxide containing copper (1). The latter is seen as a precipitate.
As Benedict's test. |
Starch
This is only slightly soluble in water, in which it forms a colloidal suspension. It can be tested in suspension or as a solid.
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Test |
Observation |
Basis of test |
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Iodine/potassium iodide test Add 2mL 1% starch solution to a test-tube. Add a few drops of I2/KI solution. Alternatively add the latter to the solid form of starch. |
A blue-black colouration |
A polyiodide complex is formed with starch. |
Lipids
Lipids include oils (such as corn oil and olive oil), fats and waxes.
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Test |
Observation |
Basis of test |
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Sudan III Sudan III is a red dye. Add 2mL oil to 2mL of water in a test-tube. Add a few drops of Sudan III and shake. Emulsion test Add 2mL fat or oil to a test-tube containing 2mL of absolute alcohol. Dissolve the lipid by shaking vigorously. Add an equal volume of cold water. |
A red-stained oil layer separates on the surface of the water, which remains uncoloured.
A cloudy white suspension. |
Fat globules are stained red and are less dense than water.
Lipids are immiscible with water. Adding water to a solution of the lipid in alcohol results in an emulsion of tiny lipid droplets in the water, which reflect light and give a white, opalescent appearance. |
Proteins
A suitable protein for these tests is egg albumen.
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Test |
Observation |
Basis of test |
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Biuret Test Add 2mL protein solution to a protein solution to a test-tube. Add an equal volume of 5% potassium hydroxide solution and mix. Add 2 drops of 1% copper sulfate solution and mix. No heating is required. |
A mauve or purple colour develops slowly. |
A test for peptide bonds. In the presence of dilute copper sulfate in alkaline solution, nitrogen atoms in the peptide chain form a purple complex with copper (II) ions (Cu2+). Biuret is a compound derived from urea, which also contains the:CONH-group and gives a positive result. |
This letter would form the beginning of a group research project into various instruments and techniques that are used by forensic chemists. To present a sales pitch, field any questions and produce an advertising brochure to promote their particular product, the groups would be required to make comprehensive research as to the basis of the technology, how it works and what it is used for. This project, and the subsequent presentations and pooling of information are designed to fulfil much of one of the seven major dot points. (number 6 : microscopic analysis)
Laboratory Technologies Pty Ltd.
Sydney Australia
Ph: 99450585 Fax: 99482435
Dear Applicant,
I am writing to inform you that your application for the position of sales representative at the esteemed Laboratory Technologies has been successful. Congratulations. We welcome you to our team and look forward to your upcoming contribution to our company.
As you start immediately, I would also like to take this opportunity to inform you of your first sales task. You will be required to provide a comprehensive overview of one of our new instruments : a [substitute appropriate instrument] Our sales plan involves representatives, such as yourself, providing a comprehensive presentation on items of equipment at various laboratories that may be interested in purchasing our products. Your first task is to prepare a presentation on the benefits for analytical chemists of a [insert instrument], as your first presentation will be at [School Name] Laboratories, on the [due date]. In your presentation it will be important to highlight 1. The usefulness of this instrument in analysis of small samples, 2. Methods by which it operates and the underlying principles, 3. The advantages of this piece of equipment.
We pride ourselves on the succinct and comprehensive nature of our presentations and the degree of familiarity of our sales staff with the product : we trust that this tradition will be upheld by yourself. Professionalism and clarity are also highly valued, and we recommend the use of a summary overhead transparency in your presentation. As well as the presentation you will also need to leave an advertising flyer at the laboratory, promoting the benefits of the equipment and its potential use for the scientists. This advertising material is crucial in gaining customers, thus our expectations of your work are high.
Again, congratulations, and best of luck in your new position.
Kind Regards
Mr. D. N. Aye
Manager of sales
Laboratory Technologies Sydney
Australia Ph: 99450585 Fax: 99482435
Berry, A. (1989). Eureka and other stories. A book of scientific anecdotes. London: Harrap books.
Good for short historical anecdotes.
Borgford, C.L.and Summerlin, L.R. (1988). Chemical activities teachers edition. Washington: American Chemical Society.
This has lots of easy-to-follow practicals that would address some of the expected practicals in the syllabus. Highly recommended.
Bursztynski, S. (1995). Potions to pulsars. Women doing science. Sydney: Allen and Unwin.
Contains story of Rosalind Franklin and her work on the structure of DNA. Good to include if discussing Watson and Crick and the race to discover the structure.
Carswell, D. J., Newman, B. C., Mihkelson, A. E. (1988). Fundamentals of senior chemistry. (2nd ed.). Melbourne: Heinemann.
Clear section on emission spectra and carbon chemistry.
Carter, M. & Cross, R. (1985). Topics in senior chemistry. Melbourne: Heinemann.
Designed to cover necessary senior chemistry topics and their prescribed practicals from the old syllabus. While not all useful contains clear experimental outlines for some of the practicals required by the forensic chemistry elective.]
Cross, R. and Carter, M. (1985). Topics in senior chemistry. Victoria: Heinemann Educational Australia.
Crowther, B. and Freemantle, M. (1991). Experiments and investigations in chemistry. Oxford: Oxford University Press.
A useful background to organic chemistry with a historical approach. Good practicals for the chromatography of starch and its hydrolysis. Flame tests.
Deretic, G. and Ware, G. (1995). Senior chemistry practical manual. Port Melbourne, VIC: Rigby Heinemann.
This was an excellent resource for practicals with senior chemistry. They are clear and easy to follow for the teacher. Lots on organic chemistry, testing for carbohydrates, protein, separating sugars by chromatography. An excellent section on visible spectra with a practical using a spectroscope and gas discharge tubes. Flame tests.
Evans, C. (1996). The casebook of forensic detection. NewYork: John Wiley and sons.
Highly readable and informative. Lots of case stories that could be used in class for motivation/interest.
Fisher, D. (1995). Hard evidence: How detectives inside the FBI's sci-crime lab have helped solve America's toughest cases. New York: Simon and Schuster.
Very readable and interesting- again, like Evans(1996), is very good.
Forensic Science. (1975). Chemistry in Britain. 11(12), 434-451.
Whole issue on aspects of forensic science. Focuses on British system of investigation. Instrumentation information still relevant despite the date.
Green, N.P.O., Stout, G.W., and Taylor,D.J. (1990). Biological Sciences 1 & 2. Cambridge: Cambridge University Press.
Chapter has good information on peptide bonds and has a comprehensive list of proteins their uses and where they are found. It also contains information on tests for proteins.
Green, N. (1996). Biological science vol 1 and 2. Cambridge: Cambridge University Press.
Text assumes a great deal of background knowledge. Good table for functions of lipids other than fats and oils. Has an experiment for detecting carbohydrates, proteins, lipids and Vitamin C.
Halliday, D., Resnick, R. and Walker, J. (1993). Fundamentals of physics (4th ed.). New York: John Wiley and sons.
Information for spectroscopy.
Kurland, M. (1995). How to solve a murder. The forensic handbook. New York: Macmillan.
A book useful mainly for its retelling of real life cases where forensic evidence was important. Also highlights the range of techniques and their applications. Contains a helpful bibliography of further resources.
Manahan, S. E. (1982). General applied chemistry. (2nd ed.). Boston: PWS Publishers.
A relatively old book, yet contains a progressive chapter entitled "Chemistry and Crime" which discusses the role of chemistry in forensics, evidence and various methods used in analysis. Good as an information source pitched at a suitable level. It contains no practicals, but these could be chosen to correspond to some of this material.
Lane, B. (1992). The encyclopedia of forensic science. Great Britain: Headline Book Publishing.
Useful for main terms used in forensic science. A good starting point if unused to the subject and terminology. Lots of useful information on different types of instrumentation presented clearly.
Newspaper clippings of well known investigations (e.g. OJ Simpson, Azaria Chamberlain, Wee Waa)
Highly useful both to elucidate the role of the FC, the methods used and to put this topic into a contemporary, real life setting.
Selinger, B. (1998). Chemistry in the marketplace. (5th ed.). Sydney: Harcourt Brace.
Useful segments in the chapters on "chemistry in the garden" : soils, trace elements, and "chemistry of paints, adhesives, enamels and concrete.
Simpkins, J., Williams, J.I. (1992). Advanced biology (3rd ed.). London: Colins Educational.
Good diagrams of triglycerides and phospholipids.
Smith, R. (1996). Conquering chemistry. (2nd ed.). Sydney: McGraw-Hill.
Not contextualised, but clear summaries of important, necessary information : such as structure and distinguishing tests for organic compounds and flame tests of inorganics.
Solomon, E. and Berg, L. (1999). Biology (5th ed.). Orlando: Saunders College Publishing.
Great and easy to understand.
Taylor, D. and Jones, M. (1994). Foundation biology. Cambridge: Cambridge University Press.
Basic and easy to understand text. Good molecular model diagrams of saturated and unsaturated fatty acids.
Thickett, G. (1996). Pathways to chemistry. Melbourne: Macmillan Education Australia.
A good senior chemistry text, although a little hard at times. Has some useful information and questions on spectroscopy.
Tortora, G., Grabowski, S. (1996). Principles of anatomy and physiology. New York: Harper Collins.
Clear summaries of DNA structure, composition and analysis techniques.
Wright, M., Perry, L., Tibbertsma, T. and Russell, D. (1992). Science in society. Milton, QLD: Jacaranda Press.
This is an excellent resource for senior science students. Has a chapter on forensic science with
some more advanced practicals and information than in junior texts. Would still be good for stage 4/5 syllabus. Chapter 12 on "Food Science" has excellent basic information on carbohydrates, proteins and fats.
ILPAC Unit 4 Independent Learning Project for Advanced Chemistry: Big Molecules. (1984) John Murray Publishers Ltd.
Page 40 has an a test for proteins. Pages 43-47 have information on chromatography and outline a paper chromatography experiment on amino acids.
Biological Science : The Web of Life. (1977) Teacher's guide Part 2. Australian Academy of Science Camberra ACT.
Pages 151 has information on a gel chromatography using plant pigments.
Biological Science : The Web of Life. (1983) Student's manual Part 2. Australian Academy of Science Camberra ACT.
Pages 232-233 outline the procedure for the gel chromatography of plant pigments.
http://www.diab.com/analyt.htm
has links to various analytical chem sites
http://www.anachem.umu.se/jumpstation.htm
excellent site with many good analytical chem links. Very good for technioques
http://minyos.its.rmit.edu.au/~rcmfa/mstheory.html
explains mass spectromerty at a basic level, providing links to more sites relevant to mass spec and tutorials