Question

What must Cooper ions gain in order to transform back into a metallic form ?

Answer 1

Ans. Copper ion, Cu²⁺ is soluble in water because polar water molecules (bearing partial negative charge on its O-atoms) can form hydration shell around the positively charged Cu²⁺ cation.

A Cu-metal atom is electrically neutral and does not interact with polar water molecules. Thus, Cu-atom is insoluble in water.

Now,

            To convert Cu²⁺ ion into metallic form Cu-atom, the ion must gain electrons and get reduced.

            Cu²⁺(aq) + 2e^- ----Reduction------> Cu(s)

            Where, Cu(s) represents the solid-phase metallic Cu-atom.