Question

If a nickel rod embedded in a silver nitrate solution , what do we predict ? explain

Answer 1

Here is a simplified activity series table.
A metal will displace any metal ION BELOW it in the activity series; i.e., Al will displace Cu^2+ but Cu will not displace Al^3+.
2Al + 3Cu^2+ ==> 3Cu(s) + 2Al^3+
Cu^2+ + Al^3+ ==> no reaction.
http://www.cod.edu/people/faculty/jarman/richenda/1551_hons_materials/Activity%20series.htm