Cleaned copper wire is place inside a solution of silver(I) nitrate. Copper has a stronger tendency to become oxidised than silver. Copper metal is oxidised to copper(II) ions and the solution turns from colourless to blue. Silver(I) ions are reduced to silver metal, forming an delicate silver-grey coating on the sides of the copper wire.
2Ag+(aq) + Cu(s) = 2Ag(s) + Cu2+(aq) redox
2Ag+(aq) + 2e- = Ag(s) reduction
Cu(s) = Cu2+(aq) + 2e- oxidation
Thank you to Sophia W. for making the video
