Chemistry Cathode
In chemistry, a cathode is the electrode of an electrochemical cell at which reduction occurs; a useful mnemonic to remember this is AnOx RedCat (Oxidation at the Anode = Reduction at the Cathode). The cathode can be negative as when the cell is electrolytic (where electrical energy provided to the cell is being used to decompose chemical compounds); or positive as when the cell is galvanic (where chemical reactions are used to generate 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 electrons 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.
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