Electrode Definition and 90 Threads

  1. B

    Electrode Potential: Establishing E & Measuring Ecell

    Am I right to think that the potential established at an electrode immediately when placed in solution is given by E = E° - \frac{R \cdot T}{F} \cdot log_e(Q_{surface}) where the potential E of the electrode results from the standard electrode potential (E°) of the reaction and the reaction...
  2. B

    Chemistry Electrode potentials question

    Am I right to think that the potential established at an electrode immediately when placed in solution is given by E = E° - R \cdot T \cdot log_e(Q_{surface}) where the potential E of the electrode results from the standard electrode potential (E°) of the reaction and the reaction quotient...
  3. H

    Electrode Potentials and Redox reactions

    What is the relation between Electrode Potentials and Redox reactions ? Can we determine the relative strength of reduction of a metal by looking just at the electrode potentials ? Here is a particular thing that confuses me : We know that the standard electrode potential of Lithium is...
  4. J

    An electrolysis reaction: Silver electrode and cathode, Rochelle Salt solution

    Hi I'm new to the forum, so first I want to say hello to everyone. I have been interested in Colloidal Silver lately, and I have produced it with electrolysis in distilled water with NaCl as an electrolyte. I have used a Silver electrode and cathode for both of these experiments. I...
  5. C

    Measuring of electrode potential.

    In set-up with two half-cells and a voltmeter, the potential difference is measured using the voltmeter. But voltmeter has high resistance,which i know is still able to measure potential difference,but wouldn't it prevent electrons from flowing What i meant was,the use of voltmeter creates a...
  6. C

    Electrode potentials and Bond energy

    Homework Statement 1st question:A voltaic cell is made up of mg2+/mg half-cell and fe3+/fe2+ half-cell. Which of the following statement are correct? a.addition of water to the fe3+/fe2+ half-cell has no effect on cell emf. b.increasing the temperature has no effect on the cell emf...
  7. K

    Electrolysis of water(ion and electrode)

    I'm new to this forum, I am studying in grade 9 and I am working on my electrolysis project but I had trouble understanding about ion and electrode (this is not my homework, I just don't understand) why does positive ion attract to negative electrode, I know that positive should attract...
  8. T

    How metals set up electrode potential in water or solution verification.

    I found this article on the web, describing how metals set up electrode potential in water or solution. How I see it the whole explanation makes sense to me, but I am not sure if its the right explanation. Could someone verify this? :confused:
  9. E

    Standard Electrode Potential of Fe2+/Fe3+

    If I try to determine the standard electrode potential of Fe2+ -------> Fe3+ + e- What would be the concentrations of Fe ions ? Would I mix 1 mol/dm3 of Fe2+ and 1 mol/dm3 of Fe3+ ions ?
  10. M

    Reference Electrode: Choosing & Principal Mechanism

    How to choose an adequate reference electrode and what is the principal mechanism?
  11. P

    Understanding Electrode Potentials: Why is 1/Molarity Used in the Calculation?

    I don't know why, but I just can't figure this out. "Calculate the electrode potential for a silver filled electrode in a solution of 0.00550 M AgNO3 solution." I got that Ag+ + e- --> Ag(s) had an E* = .80V I got that the answer is E=.80 - .0592 log (1/.00550M)= .6655 V But why...
  12. J

    1 MV electrode limited by vacuum pair production?

    Hi, Someone told me that a potential of 10^6 volts is not stable because it would cause spontaneous electron-positron creation from the vacuum. Is this true? I thought one could reach higher potentials than 1000000 volts.
  13. M

    Electrolysis of aq CuCl2 with Ag electrode

    I have a question on electrolysis: In the electrolysis of aq Copper (II) Chloride using silver electrodes, what are the products? Cathode : Copper or silver are deposited here? cos both are in the solution anode : silver electrode decrease in size... with silver deposits? Am I correct?
  14. Z

    Equilibrium Constant from Electrode Potentials

    Homework Statement Evaluate the equilibrium constant for the formation of triodide ion. I2 + I- ------> I3- a 298K, if EI2|I-o = 0.6197V and EI3-|I-o=0.5355V I don't understand one thing - At equilibrium, ΔG=0 so that Eocell=0 (from the equation ΔG=-nfE) but Eocell is not zero for...
  15. J

    What is the equation for Faraday's law of electrolysis?

    Homework Statement If 3.00 10-3 kg of gold is deposited on the negative electrode of an electrolytic cell in a period of 2.62 h, what is the current in the cell during that period? Assume the gold ions carry one elementary unit of positive charge. Homework Equations delta Q/delta T...
  16. A

    Electrode Potential: How & Why It Forms

    why the electrode potential arise at the electrode in contact with its ionic solution?
  17. W

    Electric double layer near electrode and electric field between electrode

    My question about electrochemistry is best phrase via an exercise in "Intermolecular and surface forces" by Israelachvili (although this is not my homework problem!): When an electric field is applied across an electrolyte solution containing charged particles they are seen to move parallel...
  18. L

    Electrochemical investigations using a three electrode system

    Hi, I am trying to understand what's going on in a standard three electrode system such as one used in cyclic voltammetry and the functions of each of the electrodes. I.e What role does the Working, Counter and Reference electrodes play? The conclusions iv'e come to so far is that working...
  19. T

    How Do You Calculate the Impedance of a Submerged Electrode?

    [Moderator note: This is an old thread from 2010. But it sounds like a good question, so I moved it here and bumped it to the top.] Hello, this is my first post to PF. I've been trying to find out my answer in similar posts (resistance of a disk, ...) with no luck. So I would really appreciate...
  20. C

    Electrochemistry electrode labeling

    well i would like to know how do we label the electrode as negative and positive in a daniel cell. i dnt want the learn course like anode is this and cathode is this but what i want to know as to what's the concept behind that labelling my book says that if the electrode has a positive...
  21. K

    Why are carbon, platinum, and gold inert in electrolysis?

    Homework Statement Why are carbon, platinum and gold inert? Homework Equations Duplet or Octet configuration The Attempt at a Solution We use inert elements such as carbon, platinum and gold as the electrodes to prevent the electrodes react with the electrolyte. As far as I know...
  22. A

    To measure the capacitance of interdigitated metal electrode

    Hi, Could someone give me some basic idea or information 1. How to measure the capacitance of interdigitated metal electrode of about 250 nm wide and 2 mm long on a silicon wafer, spacing between the electrode is 250 nm which is bonded bonded to copper pads. 2. Is it possible to measure the...
  23. X

    Field line near the electrodes for the different electrode

    1. Can someone explain the density of the field line near the electrodes for the different electrode. 2. How would the different field densities described above affect the force on a charge?
  24. T

    EMF and standard electrode potential

    Homework Statement This question is my translation but there should be all info needed. First part: Calculate the emf and standard electrode potential of the cell Zn/ZnO/KOH(aq)/Ag2O/Ag ZnO(s)+H2O(l)+2e- =>Zn(s)+2OH-(aq) E=-1,26V Ag2O(s)+H2O(l)+2e- =>2Ag(s)+OH-(aq) E=0,342V...
  25. L

    How to Decrease the Electric Field in a Vacuum Photodiode Circuit?

    Electrode Voltage Difference Homework Statement A vacuum photodiode is constructed by sealing two electrodes in a vacuum tube. The electrodes are separated by L and connected to a battery and a resistor (R). The potential difference between the cathode and anode is approximately equal to...
  26. K

    Electrode Potential: Manganate(VII) vs Dichromate(VI) for Fe(II) Titration

    Homework Statement Suggest why manganate(VII), rather than dichromate(VI) is used to titrate with Fe(II) in volumetric analysis. The Attempt at a Solution i have figured out 2 possible answers but both may not be correct... 1. the colour change is sharper with manganate (purple to...
  27. S

    Charge carrier concentration measurements in working electrode

    Dear All I will be grateful for any idea on how to measure electrochemically the charge carrier in an electrode say working electrode made of Al. Thank you from advance Shay
  28. S

    Electrochemistry: Stability test of reference electrode

    Dear subscribers Re: Stability test of reference electrode One of the important properties of reference electrode is its stability during measurements or potential scan. How one can check its stability in a certain electrochemical system? One of the way is to use internal reference...
  29. S

    Capacitance of point charge electrode

    Consider a capacitor which is just like a plate capacitor, but instead of the upper electrode being a plate it is a point charge Q. the lower plate is held at a fixed potential V=0. how could you calculate the capacitance of the system? when trying to calculate - it looks like it will be 0...
  30. M

    Help me - Force in x direction for a parallel plate electrode?

    Homework Statement I've two parallel plate as in attachment. The electrode area is A, when voltage are supply to the electrode, electrostatic force will be generated. Homework Equations Here, I would like to find the solution or equation of the generated force in x or y direction...
  31. H

    Fluoride Ion selective electrode measurements

    Does anyone know why we prepare F- containing solutions with plastic beakers and cups instead of the regular glass beakers before measuring the responses with F- ion selective electrode Is it because F- in corrosive? where can i find infomation on this? Thanks a lot~
  32. E

    Determining CMRR for an op amp with two electrode inputs

    Homework Statement I have an op amp with two electrode inputs. Each input has 5V of common 60 Hz noise. The size of the signal I want to measure is 9 mV. Signal to noise ratio needs to be 10 to 1. Homework Equations I know that CMRR = 20 log (DMG/CMG), where DMG is differential mode...
  33. A

    Double Ring Electrode Trap: Build Project

    I am trying to built a double ring electrodynamic trap for aerosol particles. Please suggest me for this project. Thanks
  34. P

    Electrode Sign: + or -? Understanding Cell Potential

    Electrodes in cells usually have a sign of either + or - My textbook talks about the + as because the electrode is positively charged and - when negatively charged. But is that correct? The electrodes are meant to be conductors and shouldn't be charged at any time. When they do, the ions...
  35. P

    Iodine Electrode in Battery Cell - Can I2 be Used?

    In a battery cell, let iodine (I2) be the oxidant. In this half cell, what could the electrode be? Could it have an I2(solid) coating so when it accepts electrons, it will form iodide and fall into the solution? I recall I2 was a solid. But what physical form would iodide (I-) be? It will try to...
  36. C

    What Is the Potential of an Ag/Ag+ Electrode in NaCl Solutions?

    Hello everybody I would like to know the potential of two electrode. 1- The first is the electrode of Ag/Ag+ in a saturated solution of NaCl I think that the pKs of AgCL is 9.8 (is it right?) So E= E0+0.06log[(Ks)1/2] E=0.8-0.506 E=0.506 vs ENH Is it correct? (in a book I found a...
  37. B

    Electrode Potential: Zinc-Copper E Cell & Plausibility

    When we work out the E cell of with the electrode potential values of Zinc and copper (for example) Why does a positive E cell value indicate that the reaction is plausible?
  38. S

    Electrode Potentials and Complexing

    The standard electrode potential of a Cu/Cu^2+ half-cell is given as 0.34V. However, the half-cell will only have this electrode potential relative to the hydrogen electrode when the concentration of Cu^2+ ions is 1mol.dm^-3. But won't most of the aqueous Cu^2+ ions form complexes...
  39. S

    Buying either a stick electrode arc welder

    i am looking into buying either a stick electrode arc welder or a semi-automatic flux spool fed arc welder does anyone have suggestions about using either/or? thanks
  40. S

    Solving My Copper Electrode Problem with TPD

    Hi, I have a problem with copper electrodes. I spin-coat TPD on them and due to differences in work function of the copper(4.7eV) and TPD(5.4eV) I do not get almost any current from such a system. You can take a look at TPD here...
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