Page 13 - Curriculum Visions Dynamic Book

Laboratory electrolysis
A demonstration of electrolysis can be done using
a beaker and two copper strips. A dry battery serves as the source of electrical current. The electrolyte is reagent quality copper sulphate solution.
Signs of corrosion and plating are evident within minutes, and a completely corroded strip can be produced within a day or so.
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. slag: a mixture of substances that are waste
products of a furnace.
Battery
 The process of electrolysis is shown here in a laboratory demonstration using two copper electrodes and copper sulphate solution as the electrolyte.
Copper sulphate solution
Anode
 After a few hours the anode has corroded during electrolysis. By contrast, the cathode has been plated with pure copper.
Pure copper deposited on the cathode.
Also...
In the process of refining copper
by electrolysis, several rare metals such as silver and gold are also obtained from the ore. The recovery of these helps to pay the huge cost of electrical energy used to refine copper.
Cathode on which the metal is deposited
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