Page 19 - Curriculum Visions Dynamic Book

anode: the negative terminal of a battery or the positive electrode of an electrolysis cell.
cathodic protection: the technique of making the object that is to be protected from corrosion into the cathode of a cell. For example, a material, such as steel,
is protected by coupling it with a more reactive metal, such as magnesium. Steel forms the cathode and magnesium the anode. Zinc protects steel in the same way.
electrode: a conductor that forms one terminal of a cell.
electrolysis: an electrical–chemical process that uses an electric current to cause the break up of a compound and the movement of metal ions in a solution. The process happens in many natural situations (as for example in rusting) and is also commonly used in industry for purifying (refining) metals or for plating metal objects with a fine, even metal coating.
electrolyte: a solution that conducts electricity.
 Zinc-based paints
One increasingly important use of zinc is in the form of high purity powder called zinc dust. This can then be incorporated in corrosion-resistant paints and other coatings. This picture shows a zinc-painted section of the Sydney Harbour Bridge, Australia.
 The photograph on the left shows a section of the trans-Alaska pipeline being installed. To protect the steel pipe underground, twin ribbons of zinc are wrapped around it in a corkscrew pattern before the pipe is buried. The pipe and zinc ribbons are further protected by encapsulation in a plastic coating.
Twin ribbons of zinc
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