Questions tagged [electrochemistry]

The branch of chemistry that deals with the study of redox reactions and how they can be applied to generate electricity (in electrochemical cells) and to carry out non-spontaneous reactions using electricity (electrolysis).

300 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
1
vote
0answers
41 views

Effect of charge density on electrolysis of dilute sulphuric acid

I am told that if electrolysis of dilute sulfuric acid is performed under high charge density, then the following reaction takes place at anode instead of evolving oxygen: $$\ce{2 HSO4- -> H2S2O8 +...
1
vote
0answers
44 views

Are the reactions in a simple cell overall exothermic? Why?

For context, I'm in high school. I'm trying to mentally connect electrolysis with the concept of energy changes and kinda having trouble. I understand the bottom line is that a simple cell converts ...
1
vote
0answers
43 views

Equilibrium cell potential question

In an attempt to wrap my head around the basics of electrochemistry I'm working my way through Wesley R. Browne's 'Electrochemistry' primer. With regards to the equilibrium potential of an ...
1
vote
0answers
30 views

Calculating Ka using Nernst Equation

I've heard multiple times that the Nernst Equation could be used to calculate K$_a$. How would one calculate the acidity constant, K$_a$, of a specific acid, using the Nernst Equation? The equilibrium ...
1
vote
0answers
25 views

Specific conductance of KCl

Question: A conductivity cell containing distilled water has a resistance of $\pu{454 k \Omega},$ while the same cell containing $\ce{KCl}$ solution prepared in the same sample of water shows ...
1
vote
0answers
30 views

What is the electrolytic bath used in gold-plating of copper articles?

The answer is $AuCl_3 + NaCN$ Now I understand that for electroplating, we need gold to be deposited on the copper article, and the electrolyte must enable that deposition. But I don’t know what is ...
1
vote
0answers
17 views

Which is the best kind of filter papers to use to extract silicon nanoparticles after acid wash, hydeophobic or hydrophilic?

I'm looking for filter papers to extract silicon nanoparticles after acid etching. I found that much of my material is get wasted with my Whatman Grade 4 filter paper. I am thinking to use membrane ...
1
vote
1answer
31 views

Reaction in Zinc-Carbon-Ammonium Chloride battery

I made a dry cell battery from zinc (Zn), carbon (C) and ammonium chloride (NH4Cl) which produced a current of 0.4 amps and voltage of 1.1V. However when I could not find the redox reaction that was ...
1
vote
0answers
34 views

What is the activation energy of a Daniell cell?

I'm having trouble finding a posted literature value for the activation energy for the Daniell cell redox reaction: $$\ce{Cu^2+ + Zn -> Cu + Zn^2+}$$ Where might I be able to find this ...
1
vote
0answers
29 views

Electrical conductivity and the limits of Kohlrausch's law

I am currently writing a lab report on electrical conductance and I realized that my partner prepared $\pu{0.1 M}$ solution instead of $\pu{0.01 M}$. Now, I am supposed to find the molar conductivity ...
1
vote
0answers
42 views

Why does changing the salt of the salt bridge effect the voltage produced in a galvanic cell?

My experiments results showed that the voltage decreases down $\pu{Group 1}$: $\ce{Cl-}$ salts in the salt bridge. All other variables were kept constant. $\ce{Zn}$ and $\ce{Cu}$ rods were used. ...
1
vote
0answers
34 views

Are there any chemical pathways or catalysts that could produce electricity from fossil fuels without combustion?

While fossil fuels are dense in energy, I have known only one way to retrieve energy from them, namely, to burn them. I wish we could have a way to get energy from them without combustion. Is there ...
1
vote
0answers
48 views

Help understanding Electrochemistry diagram

I was reading some literature when i came across the following figure and was wondering if someone could help explain it to me. I see on the vertical axis it is potential vs Li/Li+ and see that Oxides ...
1
vote
0answers
76 views

Electric fields in a galvanic cell

I have read hat there is two types of electric fields exist in galvanic cell.I understand E because of charges accumulated on electrodes but what about other E -field? What does cause this field and ...
1
vote
0answers
65 views

Why is E°(cell) not ∆E°cell?

$E^\circ_\mathrm{cell}$ is the EMF of the cell for a reaction with respect to standard hydrogen electrode (SHE). So why don't we represent $E^\circ_\mathrm{cell}$ or $E_\mathrm{cell}$ by $\Delta$ ...
1
vote
0answers
37 views

Why not create a latent heat battery?

Since latent heat is not sensible, it seems like it would be useful in creating an efficient battery. Sensible heat interferes with electron flow in standard lead-acid and other batteries. The latent ...
1
vote
1answer
281 views

Why is the peak-to-peak separation of cyclic voltammetry is 57 mV?

I'm studying CV, and I wonder if I can calculate the peak-to-peak separation of CV for a reversible redox system. I found that the separation is 57 mV on my textbook, and my teacher taught me that is ...
1
vote
0answers
31 views

Calculating Equilibrium Constant from Cell Potential at Nonstandard Temperature

I'm currently working on a problem for a general chemistry class. This is the voltaic cell given in the problem: $$\ce{Sn^4+(aq) + Cu(s) -> Sn^2+(aq) + Cu^2+(aq)}$$ $$E^\circ_{cell} = \pu{-0.21 V}$$...
1
vote
0answers
33 views

Gibbs free energy calculation for redox reaction

I was wondering if it is correct to calculate the Gibbs free energy of reaction at $P = \pu{1 atm}$ and $T = \pu{1100 K}$ using the NIST-JANAF thermochemical tables. For example, for the reaction of ...
1
vote
0answers
20 views

Can a Titanium Grade 5 alloy produced by SLM have greater 'surface area' exposed?

I was doing an electrochemical test (LPR) and Titanium Grade 5 produced by AM respassivated oxide layer faster than the specimen produced with traditional manufacturing under identical experimental ...
1
vote
0answers
42 views

“Hairy” corrosion on anodized alu-part in water

I got a water tank with a mechanical assembly in. The assembly consist of parts of anodized aluminium mounted on stainless steel plates (AISI 304). This is submerged down in fresh water. The tank is ...
1
vote
0answers
130 views

What could be causing my cyclic voltammograms to have a sloped scan?

I am running a CV (cyclic voltammogram) in a two compartment bulk electrolysis cell with pH 7 phosphate buffer (0.5 ion concentration) and a napheon membrane separating the two compartments. I'm using ...
1
vote
0answers
36 views

Can carbon dioxide be used as oxidant for iron?

Determine whether it is possible for $\ce{CO2}$ to be an oxidant for $\ce{Fe}$. Justify your choice by comparing the corresponding half reactions. I found the following half-reactions, both on ...
1
vote
0answers
160 views

Can static electricity damage solar cells?

How does static electricity damage common solar cells making them less photo reactive? At watt voltage and/or amps would change the chemistry of the common solar cell? I want to think that as long ...
1
vote
0answers
30 views

Calculate chemical potentials to find electrode Fermi level

I'm running some simple simulations of the semiconductor-electrolyte interface and I'm having a hard time figuring out the equilibrium condition. Can someone please help me with my electrochemical ...
1
vote
0answers
380 views

Does increasing the concentration of the anode electrolyte in a galvanic cell increase or decrease the voltage produced

Im in kind of a pickle here. I am using nernst equations to calculate the theoretical voltage produced for different concentrations of $\ce{Al(NO3)3}$. Reaction: $$\ce{2Al(s) + 3Pb^{2+}(aq)⟶2Al^{3+}(...
1
vote
0answers
53 views

What happens electrochemically when bird droppings corrode cars?

I think the metal of the car first goes through an acid corrosion, followed by an electrochemical corrosion. First, the uric acid in bird poop corrodes with iron: 2Fe+C5H4N4O3 -> C5N4O3Fe2+2H2. Then, ...
1
vote
0answers
285 views

How to calculate the cell potential after the reaction has operated long enough for the Fe2+ to have changed by some concentration?

Consider the cell described below at $\pu{261 K}$: $$\ce{Fe | Fe^2+ (\pu{0.925 M}) || Cd^2+ (\pu{0.981 M}) | Cd}$$ Given $E^\circ_\ce{Cd^2+ -> Cd} = \pu{-0.403 V}$, $E^\circ_\ce{Fe^2+ -> Fe} = \...
1
vote
0answers
41 views

why do I get chlorine gas production during electroetching?

I was electroetching stainless steel plates with table salt as electrolyte and the power supply was providing 5V, 6A when I placed the anode and cathode about .25 inches apart. I started smelling a ...
1
vote
0answers
31 views

Changing the CO2 concentration (adding or subtracting) inside a sealed vessel?

I am looking for a method of modifying the CO2 concentration inside a sealed container that is both precise and repeatable (C02 needs adjustment every time the container is sealed, also need to be ...
1
vote
0answers
26 views

Does the Nernst equation suggest voltaic cell voltage remains constant over time?

Say the following reactions are occurring in my voltaic cell: $$\ce{Mg->Mg^{2+} + 2e- +2.36V}$$ $$\ce{Cu^{2+} +2e-->Cu -0.34V}$$ Then, the Nernst equation would become: $$E_{cell}=2....
1
vote
0answers
129 views

What is the electrode potential at the equivalence point if concentrations of titrant and titrand are going to be zero?

Let's assume that the titrand is $\ce{Fe^2+}$ and the titrant is $\ce{Cr2O7^2-}$. Then $$E = E^\circ_\ce{Fe^{2+}/Fe^{3+}} - \frac{RT}{nF}\ln\frac{\ce{[Fe^{2+}]}}{\ce{[Fe^{3+}]}}$$ $$E = E^\circ_\ce{...
1
vote
1answer
290 views

what should be the onset potential using cyclic voltammetry?

I am working for PEM fuel cell cathode material. I am confused regarding the onset potential determination for my catalyst (CV attached, fig 1 is complete CV while fig 2 is its zoom image for clear ...
1
vote
0answers
19 views

Detection limit of selective ion electrodes

I've been studying about the selective ion electrodes and I came across a question which I seem to not be able to answer. It has to do with why the detection limit for iodide ions is lower than the ...
1
vote
0answers
33 views

Where does hydrogen evolution occur when aluminium amalgam is placed in water - aluminium or mercury?

Let's say a drop mercury is placed on clean aluminium sheet; mercury amalgam is formed. The solubility of aluminium in mercury and vise versa at room temperature is fairly low. If the entire sheet is ...
1
vote
0answers
16 views

Where to find information about galvanic deposition of various metals?

I am looking at the process to deposit Cu and Ag onto metallic surfaces using galvanic techniques. Unfortunately this works not as expected. For example I use 2 rods of Cu in a bath of CuSO4 with ...
1
vote
0answers
92 views

How does cyclic voltammetry in a electrolytic cell measure the precise oxidation potential?

From what I understand, the potential necessary to induce a current to flow in an electrolytic cell depends on both reduction potentials of the anode and cathode reactions, where E(cell) is comprised ...
1
vote
0answers
289 views

What effect does an increase in concentration of copper sulphate solution have on the rate at which copper is deposited at the cathode?

I have been studying electrolysis in school and was wondering whether a higher amount of copper sulfate solution would produce a greater mass of copper in an electrolytic cell with two copper ...
1
vote
0answers
70 views

What MnO2 and graphite do I need for making a dry cell battery?

I'm playing around with making my own dry-cell battery and I want to make sure I understand the pieces before diving into it. My plan is to make it like a layer cake: zinc sheet, paste of ...
1
vote
0answers
3k views

How does the cathode of an electrolytic cell drive the anode reaction?

Consider this electrolytic cell: In this cell, electrons from the anode of the battery travel to the cathode of the electrolytic cell, where hydrogen ions are reduced into hydrogen gas. This drives ...
1
vote
0answers
64 views

Can the choice of which reference electrode to use in a basic solution significantly affect the results?

I am performing a combined chronoamperometry/chronopotentiometry experiment in a solution of 0.1 M NaOH and with Ag/AgCl reference electrodes. I was initially told by someone that typically Ag/AgCl ...
1
vote
0answers
26 views

Relationship between Yield and Applied Potentials

This question revolves around this question from Atkins' Chemical Principles 5th ed., Chapter 13, Question 13.116: Consider the electroplating of a metal $+1$ cation from a solution of unknown ...
1
vote
0answers
33 views

What would affect the rate of recharge of a lead-acid battery?

I am trying to perform an investigation regarding lead-acid batteries and would like to specifically look into the recharging mechanism. However, I realised that this might be quite difficult since ...
1
vote
0answers
320 views

In a galvanic cell, do the ions from half cell move into the salt bridge?

I know that ions from salt bridge move into the half cell in order to maintain electrical neutrality. But in my book it's also given that ions move from half cell into the salt bridge. For example, ...
1
vote
0answers
52 views

Mechanism of hydrogen evolution on metal-oxide electrodes

I am looking into the mechanism of different electrocatalytic reaction in acidic media on metal-oxide electrodes. Reduction of on such electrodes generally happens with the help of electrons from ...
1
vote
0answers
141 views

Cation falling off electrode after electrolysis

I'm trying to find the electrochemical equivalent for zinc in an experiment. I am carrying out electrolysis of zinc sulfate solution. According to Faraday's law, m=zq. I made a 0.1 M solution and ...
1
vote
0answers
290 views

Reduction potential of a complex

I am given the reduction potential of $\ce{Fe^{3+}}$ to $\ce{Fe^{2+}}$ as well as the dissociation constants $\ce{K_D}$ for a $\ce{Fe^{3+}}$ complex and a $\ce{Fe^{2+}}$ complex (effectively, the ...
1
vote
0answers
536 views

Rationalising the trend of standard electrode potentials between the +II and +III oxidation state of first-row transition metals

Trends in standard electrode potentials of d block elements: An examination ofthe $E^0 (\ce{M^3+}/\ce{M^2+})$ values (Table 8.2) shows the varying trends. The low value for Sc reflects the ...
1
vote
0answers
42 views

Understanding Galvanic Cells

I am an electronics guy and not into chemistry so please forgive my ignorance. A Galvanic Cell is meant to act like a pump, separating positive and negative charges, and thereby creating an EMF. ...
1
vote
0answers
157 views

Problem in anode in experiment of electrolysis of brass

I am studying the electrolytic determination of copper content in brass (~58% copper, ~40% Zn and other trace elements) by using standard method BS EN 16117-1:2011. Now the electrode used for the ...