What is Electrochemical: Definition and 65 Discussions

Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential, as a measurable and quantitative phenomenon, and identifiable chemical change, with either electrical potential as an outcome of a particular chemical change, or vice versa. These reactions involve electrons moving between electrodes via an electronically-conducting phase (typically, but not necessarily, an external electrical circuit such as in electrolessplating), separated by an ionically-conducting and electronically insulating electrolyte (or ionic species in a solution).
When a chemical reaction is effected by a potential difference, as in electrolysis, or if electrical potential results from a chemical reaction as in a battery or fuel cell, it is called an electrochemical reaction. Unlike chemical reactions, in electrochemical reactions electrons (and necessarily resulting ions), are not transferred directly between molecules, but via the aforementioned electronically- and ionically-conducting circuits, respectively. This phenomenon is what distinguishes an electrochemical reaction from a chemical reaction.

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  1. R

    Can Electrochemical Degreasing be Affected by Chlorides and Soap?

    Hi, Why contamination of the bath for electrochemical degreasing by chlorides or soap adversly affects degreasing of parts? What's the difference if chlorine is produced instead of hydrogen or oxygen? I thought that this gases only help the grease to break away from the part's surface. I'm...
  2. il postino

    Chemistry Calculate the activity of the chloride ion in a solution

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  3. Yeahaight

    Chemistry Is bronze tarnish electrochemical corrosion or chemical corrosion?

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  4. cianfa72

    Galvanic cell - open circuit voltage and EMF

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  5. L

    Potentiostat and powersource in electrochemical cell

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  6. K

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  7. T

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  8. fsonnichsen

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  9. mishima

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  10. muzcategui

    Hello, i with lab equipment for electrochemical harvesting of microalgae

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  11. cyberdiver

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  12. JasonSpata

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  13. M

    Exploring the Future of Fuel Cells: A Ph.D Student's Perspective

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  14. Logan Johnston

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  15. B

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  16. AnkurGarg

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  17. B

    Electrochemical potential and negative Hall resistance

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  18. M

    Electrochemical Cells (involving partial pressures and pH)

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  19. S

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  20. R

    Schools Graduate school for Materials Engineering? (Electrochemical?)

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  21. K

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  22. K

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  23. Z

    Electrochemical reduction of Hydrogen forms hydride?

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  24. C

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  25. N

    Why is the potential changing in my electrochemical cell setup?

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  26. D

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  27. M

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  28. U

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  29. S

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  30. T

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  31. S

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  32. C

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  33. M

    Can this electrochemical reaction be explained? Steel, copper and electricity

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  34. G

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  35. M

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  36. A

    What ions produce a 2.00 V potential in an electrochemical cell?

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  37. N

    Charging an electrochemical capacitor

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  38. G

    How to build a circuit for an electrochemical to extract different metals

    Hello All, I am trying to build what is essentially an electrochemical cell which I will use to filter waste water and try to recover gold silver and copper among other metals on a High Surface Area Cathode like Carbon.I want this electronic filter to be selective about the metals recovered...
  39. T

    Can an Electrochemical Cell Without a Conductor Produce Voltage?

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  40. F

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  41. A

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  42. D

    Electrochemical Cells - oxidants and reductants

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  43. Topher925

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  44. Simfish

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  45. G

    Electrochemical Cells, Cell Potentials: Using Nernst Equation

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  46. R

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  47. L

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  48. L

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  49. N

    Electrochemical Cell | 75W Bulb | 50min | 12V Battery

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  50. N

    RC Charge/Discharge for Electrochemical Capacitor

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