Copper is a transition metal. It is soft, easily bent and it is a good conductor of electricity. This makes copper useful for electrical wiring. Copper does not react with water, which makes it useful for plumbing.
Copper is purified by electrolysis. Electricity is passed through solutions containing copper compounds, such as copper sulfate (sometimes spelt sulphate). As the diagram shows, pure copper forms on the negative electrode (the cathode).
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