The electron configuration of copper cation:
₂₉Cu²⁺ 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁹ or [Ar] 3d⁹.
The electron configuration of copper cation:
₄₇Ag⁺ 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ or [Kr] 4d¹⁰.
Copper and silver lose their outer s-orbital electrons before they lose their outer d-orbital electrons.
Each electron configuration is consistent with the color, copper solution is blue, silver solution is colorless.
