Standard hydrogen electrode definition of Standard hydrogen electrode in the Free Online Encyclopedia.

hydrogen electrode [′hī·drə·jən i′lek‚trōd]

(physical chemistry)

A noble metal (such as platinum) of large surface area covered with hydrogen gas in a solution of hydrogen ion saturated with hydrogen gas; metal is used in a foil form and is welded to a wire sealed in the bottom of a hollow glass tube, which is partially filled with mercury; used as a standard electrode with a potential of zero to measure hydrogen ion activity.

Hydrogen Electrode

a platinum plate coated with an electrodeposit of platinum black that is immersed in an acid solution having a specific concentration of hydrogen ions H⁺ and bathed in a flow of gaseous hydrogen. The potential of the hydrogen electrode is produced by the reversible reaction . An equilibrium is established between the hydrogen adsorbed by the platinum black and the hydrogen ions in the solution. The potential on the electrode E is determined from the Nernst equation

where T is the absolute temperature (°K), a_H+ is the active concentration of hydrogen ions (g-ion/l), p is the hydrogen pressure [kgf/cm² (atm)], and E° is the normal (or standard) potential of the hydrogen electrode when p = 1 kgf/cm² (1 atm) and a_H+ = 1. For any given temperature, E° is conventionally considered to be zero. The potentials of all other electrodes are calculated with respect to the hydrogen electrode (the so-called hydrogen potential scale). When working with a hydrogen electrode, the hydrogen must be carefully purified from admixtures. Sulfur and arsenic compounds are especially hazardous as is oxygen, which reacts with the hydrogen on the surface of the platinum to form water that disturbs the equilibrium . This electrode is employed as a reference electrode.

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No references found			Referenced to the standard hydrogen electrode scale (using E[degrees] forFc of 0. The Electrodeposition of Polypyrrole on Al alloy from room ... by Nie, Jun; Tallman, Dennis E.; Bierwagen, Gordon P. / JCT Research			standard elemental time standard error standard error of the estimate standard error of the forecast standard error of the regression coefficient standard evaporator standard extension standard fit standard for robot exclusion Standard for the exchange of product model data standard form standard free-energy increase Standard Fuel standard function standard gage standard gauge Standard Generalised Markup Language Standard Generalized Markup Language standard gold Standard Grade standard gravity standard heat of formation standard hole standard hook standard hour Standard hydrogen electrode standard I/O standard illuminants standard inductor standard input standard input/output standard inside diameter dimension ratio Standard Instrument Control Library standard interface Standard International units standard interpretation standard knot standard leak standard lens Standard Lisp Standard Load standard loran standard mapping standard mean ocean water standard measure standard meridian Standard Metropolitan Statistical Area Smsa standard mineral Standard ML Standard ML of New Jersey Standard Mode			Standard Gross Margin Standard Ground Handling Agreement Standard Ground Support Equipment Standard Guage Standard Guage Standard Hadamard-Pauli Base Standard Hamster Anterior Pituitary Homogenate Standard Hardware Acquisition and Reliability Program Standard Hardware Program Standard Header Packet Standard heat of formation Standard Heat Transfer Rate Standard Hebrew Standard Hebrew language Standard Heterosis Standard High Energy Physics Standard High Torque Motor Standard High Volume Standard Holding Pattern Standard Holding Procedure standard hole standard hook Standard Hot Plug Controller standard hour standard housing benefit Standard hydrogen electrode Standard Hydrogen Monitoring System Standard Hydrologic Exchange Format Standard Hydrometeorological Exchange Format Standard Hypermedia/Multimedia Scripting Language standard I/O standard illuminants Standard Impedance Boundary Condition Standard Implementation Documentation System Standard Implementation for Multi-Platform Link Evaluation Standard Implementation for Multi-Platform Link Exercise Standard Income Tax on Employees Standard index notation Standard index notation Standard Indexing System Standard Indirect Allowance Factor Standard Indirect Allowed Manhours Standard Individual Contribution Identifier Standard Individual Export License Standard Indonesian Rubber standard inductor Standard Industrial Classification Standard Industrial Classification Standard Industrial Classification Standard Industrial Classification Standard Industrial Classification Standard Industrial Classification Standard Industrial Classification Code Standard Industrial Classification Codes Standard Industrial Classification Coding

Hydrogen Electrode (redirected from Standard hydrogen electrode)

Hydrogen Electrode
(redirected from Standard hydrogen electrode)