Standard cell EMF from half-cell potentials (E°cell = E°cathode − E°anode (both as reduction potentials))

jee-mainjee-advancedneet-ug

E°cell = E°cathode − E°anode (both as reduction potentials)

What each symbol means

SymbolWhat it stands for
E^\circ_{\mathrm{cell}}Standard EMF of the cell (V)
E^\circ_{\mathrm{anode}}Standard reduction potential of anode half-cell (V)
E^\circ_{\mathrm{cathode}}Standard reduction potential of cathode half-cell (V)

When to use this

298 K, 1 bar, unit activities (1 M for aqueous ions). Both half-potentials must be written as reduction: oxidised form + ne⁻ → reduced form.