A.Electrolysis of molten lead(II) chloride using carbon electrodes
B.Addition of zinc powder to copper(II) sulphate solution.
C.Steam is passed over hot magnesium powder.
D.Addition of silver nitrate solution to sodium chloride solution.
This is a double decomposition reaction. It doesn't involve changes in oxidation numbers of ions.
AgNO3 + NaCl --> AgCl + NaNO3
If you calculate the oxidation numbers of each ions, they does not change before and after the reaction.
Question asked by Ryane.