Iron and steel corrode quickly in a marine environment and must be protected
Students learn to:
- identify the ways in which a metal hull may be protected including:
– corrosion resistant metals
– development of surface alloys
– new paints - predict the metal which corrodes when two metals form an electrochemical cell using a list of standard potentials
- outline the process of cathodic protection, describing examples of its use in both marine and wet terrestrial environments
- describe the process of cathodic protection in selected examples in terms of the oxidation/reduction chemistry involved
- Students:
identify data, gather and process information from first-hand or secondary sources to trace historical developments in the choice of materials used in the construction of ocean-going vessels with a focus on the metals used - identify data, gather and process information from first-hand or secondary sources to trace historical developments in the choice of materials used in the construction of ocean-going vessels with a focus on the metals used
- identify data, choose equipment, plan and perform a first-hand investigation to compare the corrosion rate, in a suitable electrolyte, of a variety of metals, including named modern alloys to identify those best suited for use in marine vessels
- plan and perform a first-hand investigation to compare the effectiveness of different protections used to coat a metal such as iron and prevent corrosion
- gather and process information to identify applications of cathodic protection, and use available evidence to identify the reasons for their use and the chemistry involved
Extract from Chemistry Stage 6 Syllabus (Amended October 2002). © 2009, Board of Studies NSW.