Standard Reduction Potential Values
Standard reduction potential values for a variety of half cells are shown in the table below. Values are expressed in volts relative to the standard hydrogen electrode (SHE). Values assume gas pressures of \(1.00\atm\), solute concentrations of \(1.00\molar\), and a temperature of \(25\unit{\degreeCelsius}\). Learn more on our Tutorial page.
The below table lists the Cathode (Reduction) Half-Reaction and the standard potential in Electron Volts. This table is designed to be searchable by screen reader.
Use your screen reader's built in search and search for the element or compound within the cathode reduction equation. Any superscript or subscript values are inline, with the subscript coming first and the superscript coming after. Example, to skip to the double mercury +2 plus 2 electrons to get 2 mercury, you could search for either H G 2 2 + or 2 H G.
Cathode (Reduction) Half-Reaction
Standard Potential Electron Volts
\({\eLi}^{+}_{\msaq}+ e^{-} \to {\eLi}_{\mss}\)
\(3.04\)
\({\eK}^{+}_{\msaq}+ e^{-} \to {\eK}_{\mss}\)
\(2.92\)
\({\eCa}^{2+}_{\msaq}+ 2e^{-} \to {\eCa}_{\mss}\)
\(2.76\)
\({\eNa}^{+}_{\msaq}+ e^{-} \to {\eNa}_{\mss}\)
\(2.71\)
\({\eMg}^{2+}_{\msaq}+ 2e^{-} \to {\eMg}_{\mss}\)
\(2.38\)
\({\eAl}^{3+}_{\msaq}+ 3e^{-} \to {\eAl}_{\mss}\)
\(1.66\)
\({2\eH_{2}\eO}_{\msl}+ 2e^{-} \to {\eH_{2}}_{\msg}+ {2\eO\eH}^{-}_{\msaq}\)
\(0.83\)
\({\eZn}^{2+}_{\msaq}+ 2e^{-} \to {\eZn}_{\mss}\)
\(0.76\)
\({\eCr}^{3+}_{\msaq}+ 3e^{-} \to {\eCr}_{\mss}\)
\(0.74\)
\({\eFe}^{2+}_{\msaq}+ 2e^{-} \to {\eFe}_{\mss}\)
\(0.41\)
\({\eCd}^{2+}_{\msaq}+ 2e^{-} \to {\eCd}_{\mss}\)
\(0.4\)
\({\eNi}^{2+}_{\msaq}+ 2e^{-} \to {\eNi}_{\mss}\)
\(0.23\)
\({\eSn}^{2+}_{\msaq}+ 2e^{-} \to {\eSn}_{\mss}\)
\(0.14\)
\({\ePb}^{2+}_{\msaq}+ 2e^{-} \to {\ePb}_{\mss}\)
\(0.13\)
\({\eFe}^{3+}_{\msaq}+ 3e^{-} \to {\eFe}_{\mss}\)
\(0.04\)
\({2\eH}^{+}_{\msaq}+ 2e^{-} \to {\eH_{2}}_{\msg}\)
\(0\)
\({\eSn}^{4+}_{\msaq}+ 2e^{-} \to {\eSn}^{2+}_{\msaq}\)
\(0.15\)
\({\eCu}^{2+}_{\msaq}+ e^{-} \to {\eCu}^{+}_{\msaq}\)
\(0.16\)
\({\eCl\eO_{4}}^{-}_{\msaq}+ \eH_{2}\eO_{\msl}+ 2e^{-} \to {\eCl\eO_{3}}^{-}_{\msaq} + {2\eO\eH}^{-}_{\msaq}\)
\(0.17\)
\({\eAg\eCl}_{\mss}+ e^{-} \to {\eAg}_{\mss} + {\eCl}^{-}_{\msaq}\)
\(0.22\)
\({\eCu}^{2+}_{\msaq}+ 2e^{-} \to {\eCu}_{\mss}\)
\(0.34\)
\({\eCl\eO_{3}}^{-}_{\msaq} + {\eH_{2}\eO}_{\msl} + 2e^{-} \to {\eCl\eO_{2}}^{-}_{\msaq} + {2\eO\eH}^{-}_{\msaq}\)
\(0.35\)
\({\eI\eO}^{-}_{\msaq} + {\eH_{2}\eO}_{\msl}+ 2e^{-} \to {\eI}^{-}_{\msaq} + {2\eO\eH}^{-}_{\msaq}\)
\(0.49\)
\({\eCu}^{+}_{\msaq}+ e^{-} \to {\eCu}_{\mss}\)
\(0.52\)
\({\eI_{2}}_{\mss} + 2e^{-} \to {2\eI}^{-}_{\msaq}\)
\(0.54\)
\({\eCl\eO_{2}}^{-}_{\msaq} + {\eH_{2}\eO}_{\msl}+ 2e^{-} \to {\eCl\eO}^{-}_{\msaq} + {2\eO\eH}^{-}_{\msaq}\)
\(0.59\)
\({\eFe}^{3+}_{\msaq}+ e^{-} \to {\eFe}^{2+}_{\msaq}\)
\(0.77\)
\({\eHg_{2}}^{2+}_{\msaq}+ 2e^{-} \to {2\eHg}_{\msl}\)
\(0.8\)
\({\eAg}^{+}_{\msaq}+ e^{-} \to {\eAg}_{\mss}\)
\(0.8\)
\({\eHg}^{2+}_{\msaq}+ 2e^{-} \to {\eHg}_{\msl}\)
\(0.85\)
\({\eCl\eO}^{-}_{\msaq} + {\eH_{2}\eO}_{\msl}+ 2e^{-} \to {\eCl}^{-}_{\msaq}+ {2\eO\eH}^{-}_{\msaq}\)
\(0.9\)
\({2\eHg}^{2+}_{\msaq}+ 2e^{-} \to {\eHg_{2}}^{2+}_{\msaq}\)
\(0.9\)
\({\eN\eO_{3}}^{-}_{\msaq}+ {4\eH}^{+}_{\msaq}+ 3e^{-} \to {\eN\eO}_{\msg}+ {2\eH_{2}\eO}_{\msl}\)
\(0.96\)
\({\eBr_{2}}_{\msl}+ 2e^{-} \to {2\eBr}^{-}_{\msaq}\)
\(1.07\)
\({\eO_{2}}_{\msg}+ {4\eH}^{+}_{\msaq}+ 4e^{-}- \to {2\eH_{2}\eO}_{\msl}\)
\(1.23\)
\({\eCr_{2}\eO_{7}}^{2-}_{\msaq}+ {14\eH}^{+}_{\msaq}+ 6e^{-} \to {2\eCr}^{3+}_{\msaq} + {7\eH_{2}\eO}_{\msl}\)
\(1.33\)
\({\eCl_{2}}_{\msg}+ 2e^{-} \to {2\eCl}^{-}_{\msaq}\)
\(1.36\)
\({\eCe}^{4+}_{\msaq}+ e^{-} \to {\eCe}^{3+}_{\msaq}\)
\(1.44\)
\({\eMn\eO_{4}}^{-}_{\msaq}+ {8\eH}^{+}_{\msaq}+ 5e^{-} \to {\eMn}^{2+}_{\msaq}+ {4\eH_{2}\eO}_{\msl}\)
\(1.49\)
\({\eH_{2}\eO_{2}}_{\msaq}+ {2\eH}^{+}_{\msaq}+ 2e^{-} \to {2\eH_{2}\eO}_{\msl}\)
\(1.78\)
\({\eCo}^{3+}_{\msaq}+ e^{-} \to {\eCo}^{2+}_{\msaq}\)
\(1.82\)
\({\eS_{2}\eO_{8}}^{2-}_{\msaq}+ 2e^{-} \to {2\eS\eO_{4}}^{2-}_{\msaq}\)
\(2.01\)
\({\eO_{3}}_{\msg}+ {2\eH}^{+}_{\msaq}+ 2e^{-} \to {\eO_{2}}_{\msg}+ {\eH_{2}\eO}_{\msl}\)
\(2.07\)
\({\eF_{2}}_{\msg}+ 2e^{-} \to {2\eF}^{-}_{\msaq}\)
\(2.87\)
Table with Cathode (Reduction) Half-Reduction formula and the standard potential electron volts. This is a searchable table by the compounds within the half-reaction.
Cathode (Reduction) Half-Reaction
Standard Potential Electron Volts
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