Cathode
| Formula / Notation | Ox + ne⁻ → Red |
|---|---|
| Also Known As | Negative electrode (electrolytic), reduction electrode, positive terminal (galvanic) |
What is Cathode?
The cathode is the electrode at which reduction occurs in an electrochemical cell. In an electrolytic cell, the cathode is connected to the negative terminal of the power source, and cations migrate towards it to gain electrons. In a galvanic (voltaic) cell, the cathode is the positive electrode. The word derives from the Greek for "downward path".
Formula & Notation
Other Names / Synonyms: Negative electrode (electrolytic), reduction electrode, positive terminal (galvanic)
Properties & Characteristics
Uses & Applications
Safety Information
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
Key Facts
Frequently Asked Questions
The cathode is the electrode at which reduction occurs in an electrochemical cell. In an electrolytic cell, the cathode is connected to the negative terminal of the power source, and cations migrate towards it to gain electrons. In a galvanic (voltaic) cell, the cathode is the positive electrode. The word derives from the Greek for "downward path".
Cathodes are essential in electroplating, electrolytic refining, the chlor-alkali process, aluminium smelting (Hall-Héroult process), lithium-ion batteries, and fuel cells. The cathode material affects selectivity, overpotential, and efficiency of the electrochemical process.
Cathodes producing hydrogen gas create explosion risks (H₂ is flammable, 4-75% in air). Ensure adequate ventilation in electrochemical laboratories. Alkali metal deposition at cathodes (molten salt electrolysis) is highly reactive and must be handled under inert atmosphere.
The formula or notation for Cathode is: Ox + ne⁻ → Red