Component: Option - Shipwrecks, Corrosion and Conservation

Question 29

Written Paper Section I Question 29 - 2002 HSC

(a) Type of electrochemical cell producing a spontaneous reaction; voltage required to operate an illustrated cell as an electrolytic cell. (b) How the work of early scientists increased our understanding of electron transfer reactions. (c) Method for removing salt from a shipwreck artefact; chemical procedures used to clean and preserve artefacts. (d) Procedure for comparing the rate of corrosion in different acidic and neutral solutions; explain whether data supports a hypothesis that acidic environments accelerate the corrosion of shipwrecks. (e) Analyse the effect of ocean depth on corrosion of metallic objects.

Question 29

Written Paper Section II Question 29 - 2001 HSC

(a) Identify the main metal used to construct ships; explain why aluminium is used in structures exposed to oxidising conditions. (b) Identify a metal commonly used as a sacrificial anode; explain why sacrificial anodes are added to metal-hulled ships. (c) Describe the effect of adding other elements to iron on the properties and uses of steels. (d) Define corrosion;outline a procedure used to compare corrosion rates of different metals or alloys; describe ways accuracy and reliability of the procedure can be improved. (e) Evaluate steps used to clean, stabilise and preserve artefacts recovered from shipwrecks.

Question 33

Written Paper Question 33 - 2010 HSC

(a) Effect of marine environment on a wood and metal artefact. (b) Labelled diagram to show electrolysis of an aqueous solution of potassium chloride, including identification of the cathode. (c) Explanation of how different composition of steel determine properties and uses. (d) Investigation of environmental factors affecting rate of corrosion of iron. Method to reduce effect of a corrosive factor in the marine environment. (e) Suitability of techniques for restoring and conserving wooden and copper artefacts that have been immersed in saltwater for at least 100 years.