Support materials only that illustrate some possible contexts for exploring Science as a Human Endeavour concepts in relation to Science Understanding content.
Future challenges in Australia and the Asia region in resource, environmental and economic sustainability demand more efficient chemical processes. The concept of atom economy was proposed by American Barry Trost in the 1990s. It is a way of describing the efficiency of a reaction, by dividing the molecular mass of the desired product by the combined molecular masses of all reactants. Many established large-scale industrial chemical processes in the petrochemical industry have a low atom economy, resulting in unwanted byproducts and waste management issues. Green chemistry aims to increase the atom economy of chemical processes by designing novel reactions that can maximise the desired products and minimise byproducts (ACSCH126). Designing new synthetic schemes that can simplify operations in chemical productions, and seeking greener solvents that are inherently environmentally and ecologically benign, are also important in developing sustainable chemical industries (ACSCH126).
Dwindling supplies of economically viable sources of fossil fuels and concerns related to carbon emissions have prompted research into the synthesis of biofuels (ACSCH126) from plant feedstocks such as algae, oil seeds and wood waste, or from waste materials such as food industry waste oils (ACSCH126). In the 1990s, a number of plants producing biodiesel were established in Europe and biodiesel is now available at many service stations across Europe. Biofuels are more complex than petroleum-based fuels, many comprising of a range of alcohols or methyl esters. Analysis techniques such as spectroscopy and mass spectrometry can be used to investigate the combustion processes of these ‘oxygenated’ fuels, and predict any potential harmful emissions from their combustion (ACSCH123). While biofuels may address issues of renewable fuel supply, there are concerns that a focus on biomass plantations as feedstocks may result in reduced available land for food production, and an increase in food prices and availability (ACSCH126).
Molecular manufacturing (or molecular assembly) is an area of developing science that involves building objects to atomic precision using robotic mechanisms to position and react molecules (ACSCH120). A recent publication in the peer-reviewed international journal Science reported that researchers had developed a new way of developing sequence-specific peptides using a rotaxane as a ‘molecular machine’. Proponents of molecular manufacturing argue that it has the potential to quickly develop products such as stronger materials and smaller, faster and more energy-efficient computers. They claim it will address a range of global issues through provision of vital materials and products at a greatly reduced cost and environmental impact. However other groups caution that cheap, rapid manufacturing capacity could also lead to a range of social, economic and environmental issues, and requires international regulations and policies to be in place before the technology becomes widely available. Some scientists predict that a ‘molecular manufacturing revolution’ will occur within the next 20 to 50 years, while others are sceptical that the methods used will ever become economically viable (ACSCH124).