MAKING SENSE OF THE MATERIAL WORLD: LEVEL 8
ACHIEVEMENT OBJECTIVES
Students can
- carry out an extended investigation involving a range of techniques, originating from their own interests, into some aspect of, or issue related to, the Material World;
- investigate and relate the chemical and physical properties (of increasing complexity) of a family of substances to their use in the home, industry, and the environment, e.g., organic acids, mineral acids, metal cations, detergents;
- further investigate chemical processes by manufacturing a commonly used substance and comparing its properties with a similar commercial product, e.g., aspirin, paint, food products, perfumes;
- research the functions and use of selected groups of chemicals and describe some effects of these on people and the environment, e.g., alcohols, food additives, emulsifiers, radio-isotopes, heavy metals, CFCs, agricultural chemicals, trace elements.
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Note: Teachers should recognise the opportunity for students to take an integrated approach to achieving objective 1 by combining their learning from this and other contextual learning strands in a single investigation. This approach could reduce the number of extended investigations students would carry out.
SAMPLE LEARNING CONTEXTS
- Nuclear power
- Nga toa hokomaha
- Food irradiation
- Miti tahu
- Sports medicine
- Manufacturing plants
- Gardening centres
- Hardware
- Nga whakaahua whakaroto
- Supermarkets
- Kumara tao
- I roto mara
- Breweries
- Fertiliser works
- Plastics manufacturing
- Dairy factories
- Water treatment plants
- Atmospheric pollution
POSSIBLE LEARNING EXPERIENCES
Students could be learning by:
- investigating methods of food preservation in New Zealand, from traditional Māori methods to contemporary methods;
- investigating the mediation of naturally occurring enzymes in the breakdown of nitrogen-based fertilisers;
- investigating the biochemistry of muscle contraction;
- investigating the composition of household cleaners and exploring possible links between the findings and their efficiency as antibacterial disinfectants;
- investigating the manufacture and efficiency of synthetic fuels;
- investigating the properties of some viscous liquids and exploring possible links between the findings and the flow and distribution of materials from volcanoes;
- considering the effect of changing temperature and pressure on equilibria when manufacturing a soap;
- making a fertiliser, such as ammonium sulphate, and testing its pH;
- becoming familiar with the methods of expressing the amount and concentration of chemical substances, e.g., ppm, g/l, moles, mol/l, to practise simple quantitative measurements and techniques;
- analysing the amount of acetic acid in a range of commercial vinegars;
- titrating a range of commercially and domestically produced diluted fruit juice with sodium hydroxide to determine total acid content;
- researching the chemistry involved in the synthesis of steroids and their effect on the body when used in sport and contraception;
- interviewing farmers about the trace elements needed on their farms to determine some of the beneficial effects of chemicals on the environment;
- distinguishing between the greenhouse effect and ozone depletion to study the effect of a group of chemicals on the environment;
- designing and building an alternative to a pressurised aerosol can to discover alternative solutions to environmental problems;
- critically analysing a media report on the use of tributyl tin as a keel defoliant.
ASSESSMENT EXAMPLES
Teachers and students could assess the students':
- understanding of how the use of a substance is determined by its properties, when the students research and report on the use and effects of ethyl alcohol;
- understanding of the chemical function of preservatives, when the students give a seminar on techniques used for food preservation;
- ability to carry out a rigorous, systematic investigation, when the students present a report on their manufacture of a product and its fair testing against a similar commercial product;
- understanding of the processes involved, when the students present a laboratory report on the manufacture of aspirin from methyl salicylate (oil of wintergreen);
- quantitative analysis techniques, when the students analyse the amount of sodium bicarbonate in baking powder by gravimetric analysis;
- understanding of the origin and effects of a pollutant, when the students demonstrate qualitatively the presence of lead in petrol and describe its effects on the human body.
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