Purifying Copper

Copper is purified using electrolysis, an energy-intensive process. The setup involves a pure copper sheet at the cathode and an impure sheet at the anode, with copper sulfate as the electrolyte. Copper ions move between the anode and cathode, allowing oxidation and reduction. At the cathode, copper ions are deposited, increasing its size, while the anode dissolves, leaving behind sludge containing valuable metals like silver and gold. The process maintains the solution's concentration, and the copper sulfate solution is replaced if zinc ions accumulate.

What is the primary purpose of using electrolysis in copper purification?

• To purify copper for use as an electrical conductor

• To make copper more malleable

• To increase the weight of copper

• To change the color of copper

During electrolysis, what happens to the size of the cathode?

• It gets larger

• It remains the same

• It becomes smaller

• It changes color

What is left behind at the anode as it dissolves?

• Zinc ions

• Copper sulfate

• Anode sludge

• Pure copper

Why might industries choose not to discard anode sludge immediately?

• It is hazardous waste

• It contains valuable metals like silver and gold

• It can be reused as an electrolyte

• It is too expensive to dispose of

What action is necessary if the concentration of zinc ions in the solution becomes too high?

• Increase the current

• Add more copper sulfate

• Replace the copper sheets

• Replace the copper sulfate solution