Search results
Results from the WOW.Com Content Network
The terms anode and cathode are not defined by the voltage polarity of electrodes, but are usually defined by the direction of current through the electrode. An anode usually is the electrode of a device through which conventional current (positive charge) flows into the device from an external circuit, while a cathode usually is the electrode through which conventional current flows out of ...
In a vacuum tube or a semiconductor having polarity (diodes, electrolytic capacitors) the anode is the positive (+) electrode and the cathode the negative (−). The electrons enter the device through the cathode and exit the device through the anode. Many devices have other electrodes to control operation, e.g., base, gate, control grid.
Diagram of a copper cathode in a galvanic cell (e.g., a battery). Positively charged cations move towards the cathode allowing a positive current i to flow out of the cathode. A cathode is the electrode from which a conventional current leaves a polarized electrical device such as a lead-acid battery.
The cathode is the electrode where reduction (gain of electrons) takes place (metal B electrode); in a galvanic cell, it is the positive electrode, as ions get reduced by taking up electrons from the electrode and plate out (while in electrolysis, the cathode is the negative terminal and attracts positive ions from the solution).
When a battery is supplying power, its positive terminal is the cathode and its negative terminal is the anode. [2] The terminal marked negative is the source of electrons. When a battery is connected to an external electric load, those negatively charged electrons flow through the circuit and reach to the positive terminal, thus cause a redox ...
The driving force for the cathodic protection current is the difference in electrode potential between the anode and the cathode. [9] During the initial phase of high current, the potential of the steel surface is polarized (pushed) more negative protecting the steel which hydroxide ion generation at the steel surface and ionic migration ...
Electrochemical cells have two conductive electrodes (the anode and the cathode). The anode is defined as the electrode where oxidation occurs and the cathode is the electrode where the reduction takes place. Electrodes can be made from any sufficiently conductive materials, such as metals, semiconductors, graphite, and even conductive polymers.
Likewise, he defined the anode as the electrode to which anions (negatively charged ions, like chloride ions Cl − ) flow within the cell, to be oxidized by depositing electrons on the electrode. To an external wire connected to the electrodes of a galvanic cell (or battery), forming an electric circuit, the cathode is positive and the anode ...