E

Electrode Potential

E = E° − (RT/nF)ln Q
Quick Reference
Formula / NotationE = E° − (RT/nF)ln Q
Also Known AsReduction potential, standard electrode potential (E°), half-cell potential, EMF

What is Electrode Potential?

The potential difference between an electrode and the electrolyte solution, measured relative to a standard reference electrode. The standard hydrogen electrode (SHE) is assigned a potential of 0.00 V. Electrode potentials are used to predict spontaneity of redox reactions.

Formula & Notation

E = E° − (RT/nF)ln Q

Other Names / Synonyms: Reduction potential, standard electrode potential (E°), half-cell potential, EMF

Properties & Characteristics

Electrode potential is the potential of an electrode relative to a reference electrode (typically the standard hydrogen electrode, SHE) when measured under standard conditions (E°) or non-standard conditions (E, via Nernst equation). It quantifies the tendency of an electrode to undergo reduction. The cell potential is the difference between cathode and anode potentials. Electrode potentials depend on concentration, temperature, and the nature of the redox couple.

Uses & Applications

Electrode potentials are used to calculate cell EMFs, determine reaction spontaneity, design batteries and fuel cells, and in analytical methods (potentiometry, ion-selective electrodes). They are fundamental to understanding corrosion, electroplating efficiency, and industrial electrolysis.

Safety Information

Extreme electrode potentials (large positive for oxidisers, large negative for strong reducing agents) indicate highly reactive species. Working with strong oxidising agents (peroxydisulfate, Ce⁴⁺) or strong reducing agents (Na, Li) requires specialised safety measures.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Electrode Potential
Formula E = E° − (RT/nF)ln Q
Synonyms Reduction potential, standard electrode potential (E°), half-cell potential, EMF

Frequently Asked Questions

The potential difference between an electrode and the electrolyte solution, measured relative to a standard reference electrode. The standard hydrogen electrode (SHE) is assigned a potential of 0.00 V. Electrode potentials are used to predict spontaneity of redox reactions.

More "E" Terms

View all "E" terms →
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z