Standard reduction potentials E° (volts, 298 K, vs the standard hydrogen electrode). Listed most negative → most positive. Search an element or ion.
▪ More positive E° → the species on the left is a stronger oxidising agent (F₂, MnO₄⁻, Cr₂O₇²⁻ at the bottom).
▪ More negative E° → the species on the right is a stronger reducing agent (Li, K, Ca at the top).
▪ A metal higher up displaces the ion of a metal lower down. Cell EMF = E°(cathode) − E°(anode); positive ⇒ spontaneous.
▪ The SHE (H⁺/H₂, E° = 0) is the zero reference; metal reactivity ∝ how negative E° is.
| Reduction half-reaction | E° / V | role |
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