The normal potentials of the listed metals are arranged from the highest negative to the highest positive value.

Base metals = metals with the highest negative normal potential - have a strong reducing effect and react easily with water and air.

The metal at the top of the voltage series (more negative potential) can displace a less noble metal below it from its solution, e.g., when metallic iron is added to a copper(II) salt solution: Cu2++ Fe → Cu + Fe2+.

Some base metals form protective oxide layers on their surface. That is, they behave more nobly than corresponds to their strongly negative normal potential.

The metals in the following table are listed alphabetically:

Metal Redox system Normal potential (volts)
Aluminum Al↔Al3++ 3e‾ -1.69
Antimony Sb↔Sb3++ 3e‾ +0.2
Arsenic As↔As3++ 3e‾ +0.3
Beryllium Be↔Be2++ 2e‾ -1.85
Lead Pb↔Pb2++ 2e‾ -0.13
Cadmium Cd↔Cd2++ 2e‾ -0.40
Calcium Ca↔Ca2++ 2e‾ -2.87
Chromium Cr↔Cr3++ 3e‾ -0.71
Iron Fe↔Fe2++ 2e‾ -0.44
Gold Au↔Au++ e‾ +1.68
Gold Au↔Au3++ 3e‾ +1.36
Indium In↔In3++ 3e‾ -0.34
Potassium K↔K++ e‾ -2.93
Cobalt Co↔Co2++ 2e‾ -0.28
Copper Cu↔Cu++ e‾ +0,52
Copper Cu↔Cu2++ 2e‾ +0.35
Magnesium Mg↔Mg2++ 2e‾ -2.38
Manganese Mn↔Mn2++ 2e‾ -1.05
Molybdenum Mo↔Mo3++ 3e‾ -0.2
Sodium Na↔Na++ e‾ -2.71
Nickel Ni↔Ni2++ 2e‾ -0.25
Palladium Pd↔Pd2++ 2e‾ +0.987
Platinum Pt↔Pt2++ 2e‾ +1.2
Mercury Hg↔Hg2++ 2e‾ +0.85
Mercury 2 Hg↔Hg22++ 2e‾ +0.789
Silver Ag↔Ag++ e‾ +0.799
Titanium Ti↔Ti3++ 3e‾ -1.21
Vanadium V↔V2++ 2e‾ -1.18
Hydrogen H2↔2H++ 2e‾ ±0.0
Bismuth Bi↔Bi3++ 3e‾ +0.28
Tungsten W+8OH↔WO42++4H2O+6e‾ -1.10
Zinc Zn↔Zn2++ 2e‾ -0.76
Tin Sn↔Sn2++ 2e‾ -0.16