The voltage series


Definition



The voltage series is the redox table showing the metals(reductants, reducing agents) and their usual cations (oxidants, oxidizing agents) including the couple ($H^+$/$H_2$)


 
$Au^{3+}+3e^-$$Au$
$Hg^{2+}+2e^-$$Hg$
$Ag^{+}+e^-$$Ag$
$Cu^{2+}+2e^-$$Cu$
$2H^{+}+2e^-$$H_2$
$Pb^{2+}+2e^-$$Pb$
$Sn^{2+}+2e^-$$Sn$
$Fe^{2+}+2e^-$$Fe$
$Zn^{2+}+2e^-$$Zn$
$Al^{3+}+3e^-$$Al$
$Mg^{2+}+2e^-$$Mg$
$Na^{+}+e^-$$Na$
$Ca^{2+}+2e^-$$Ca$
$K^{+}+e^-$$K$
$Li^{+}+e^-$$Li$

Each oxidant (left) can react with each reductant (right) situated below

Examples


Iron and copper(II) cation:



An iron rod introduced in a solution of copper(II) sulfate becomes covered with a red copper layer:
$Cu^{2+}+2e^- \longrightarrow Cu$
$Fe-2e^- \longrightarrow Fe^{2+}$
______________________________
$Cu^{2+}+Fe \longrightarrow Cu + Fe^{2+}$

Copper and silver cation:



A copper sheet introduced in a silver nitrate solution becomes covered with a black silver layer:
$Ag^++e^-\longrightarrow Ag$
$Cu-2e^-\longrightarrow Cu^{2+}$
______________________________
$Cu +2Ag^+\longrightarrow Cu^{2+}+2Ag$

Zinc and lead nitrate:



Zinc pellets introduced in a lead nitrate solution becomes covered with black lead cristals:
$Pb^{2+}+2e^-\longrightarrow Pb$
$Zn-2e^-\longrightarrow Zn^{2+}$
______________________________
$Zn +Pb^{2+}\longrightarrow Zn^{2+}+Pb$