[Ar] 3d¹⁰ 4s¹

The element copper has 11 valence electrons, distributed amongst the outermost d and s orbitals.

As was shown in Figure 741.1. 2, the nucleus of the copper atom contains 29 protons. A neutral copper atom must therefore have 29 electrons distributed amongst its various shells. Shells k, 1, and m are filled to capacity with a total of 28 electrons, so there is only one electron in the n shell.

So as you are saying copper is unreactive, it as reacting in cytochrome oxidase in every mitochondrion of your body, and in Cu/Zn superoxide dismutase in the cytosol of cells through your body. Looking at this list, we see that there are a substantial number of d-block metals that are less reactive than copper.

List of elements with electrons per shell

Electronic configuration of Cu is 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d9 ([Ar] 4s2, 3d9), whereas for Cu2+ is [Ar], 3d9.

1. Copper atoms in a metal have no charge, but copper ions in solution as copper chloride have a positive charge.

Cu(III) ion.

(f) What happens if the leads to the copper and zinc electrodes are switched? The direction of current flow through the meter is reversed, and the sign of the voltage reading changes. The electrodes switch function, so the zinc is reduced and the copper is oxidized, and the sign of the voltage reading changes.

Zinc behaves as the anode (supplying electrons) of the galvanic cell and the copper as the cathode (consuming electrons). The zinc electrode is dissolved (corroded or oxidized) and the copper electrode accepts copper atoms from the electrolyte (electroplating or reduction).

Generally copper and its alloys are widely used as an electrode due to its high conductivity and low cost.

Oxidation involves loss of electrons and always occurs at the anode. Zinc is therefore the anode as oxidation is occuring in the Zn2+(aq) / Zn(s) half cell. The electrons are left behind on the electrode, which becomes negatively charged. Reduction involves gain of electrons and always occurs at the cathode.

This process is called galvanic corrosion. A sacrificial anode consists of a metal alloy, such as zinc, that has a more active voltage when it is introduced into the electrolyte current. The zinc, in essence, stops the oxidation happening to the other metal part as the zinc dissolves away.

magnesium anodes

Zinc works well in saltwater and has been the traditional anode metal for a long time, but it’s also the heaviest option and is more toxic for the environment. Aluminum is lightweight and works in both salt AND brackish waters.