Editing Cathode (section)

==In chemistry==
In [[chemistry]], a '''cathode''' is the [[electrode]] of an [[electrochemical cell]] at which [[Reduction (chemistry)|reduction]] occurs. The cathode can be negative like when the cell is electrolytic (where electrical energy provided to the cell is being used for decomposing chemical compounds); or positive as when the cell is galvanic (where chemical reactions are used for generating electrical energy). The cathode supplies electrons to the positively charged cations which flow to it from the electrolyte (even if the cell is galvanic, i.e., when the cathode is positive and therefore would be expected to repel the positively charged cations; this is due to [[electrode potential]] relative to the electrolyte solution being different for the anode and cathode metal/electrolyte systems in a [[galvanic cell]]).

The '''cathodic current''', in [[electrochemistry]], is the flow of [[electron]]s from the cathode interface to a species in solution. The '''anodic current''' is the flow of electrons into the anode from a species in solution.

===Electrolytic cell===
In an [[electrolytic cell]], the cathode is where the negative polarity is applied to drive the cell. Common results of reduction at the cathode are hydrogen gas or pure metal from metal ions. When discussing the relative reducing power of two redox agents, the couple for generating the more reducing species is said to be more "cathodic" with respect to the more easily reduced reagent.

===Galvanic cell===
In a [[galvanic cell]], the cathode is where the positive [[Electrical polarity|pole]] is connected to allow the circuit to be completed: as the anode of the galvanic cell gives off electrons, they return from the circuit into the cell through the cathode.

===Electroplating metal cathode (electrolysis)===
When metal ions are reduced from ionic solution, they form a pure metal surface on the cathode. Items to be plated with pure metal are attached to and become part of the cathode in the electrolytic solution.