The following sketch represents the electroplating of an Iron cup with Nickel metal. Study the diagram and answer the following questions:
(a) During electroplating the iron cup is placed at the cathode. Why?
(b) Name the ion that must be present in the electrolyte.
(c) State one condition that is necessary to ensure that the deposit is smooth, firm and even.
(d) Write the reaction taking place at the cathode.
(e) What change would you observe at the anode?
(a) In electroplating, the cathode is the electrode where reduction (gain of electrons) occurs. The iron cup is placed at the cathode because the metal ions from the electrolyte will be reduced and deposit onto the iron cup. This process coats the iron cup with a layer of metal, achieving the plating effect.
(b) Ni2+ must be present in the electrolyte.
(c) A low current for a longer time should be used as longer time and low current initiates a thicker, uniform deposit.
(d) Ni2+ + 2e– → Ni
(e) The Nickel plate is gradually dissolved as ions in solution.
More ICSE Moderate level questions
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