Questions tagged [reduction-potential]

For questions about the reduction potential (A measure of the tendency of a chemical species to acquire electrons and thereby be reduced) or its applications. Also see the tag [electrochemistry].

Filter by
Sorted by
Tagged with
0
votes
1answer
48 views

Isolating barium(II), copper(II) and zinc(II) from aqueous solution [on hold]

Q15 Each metallic ion was separated from an aqueous solution containing $\ce{Ba^2+},$ $\ce{Cu^2+},$ and $\ce{Zn^2+}$ by the procedure shown in the following figure. From ①–⑥ in the table below choose ...
-1
votes
1answer
54 views

Question About Reversible Reactions and Batteries

So my book says that the batteries we have considered so far( Daniell cells) are low life span, because they reach equilibrium too fast. In the next paragraph, it says they are also made by ...
0
votes
1answer
24 views

In a galvanic cell,do charges accumulate on electrodes 1st (then redox occur) which produce E in the wire when we connect between electrodes? [closed]

We study that when we connect a wire between the terminals of a battery ,an electric field in established between terminals due to potential difference .Is the potential difference result of ...
2
votes
1answer
42 views

Latimer diagram for a metal in basic solution

Write the four half cell reactions from the Latimer diagram for a metal $(\ce{M})$ in basic solution. $$\ce{\overset{+6}{M}O4^2-(aq) ->[\pu{0.25 V}] \overset{+5}{M}O4^3-(aq) ->[\pu{0.55 V}] ...
0
votes
0answers
36 views

Determining the half-potential using Latimer diagram

$$\ce{\overset{+7}{Br}O4- ->[\pu{+1.82 V}] \overset{+5}{Br}O3- ->[\pu{+1.49 V}] H\overset{+1}{Br}O ->[\pu{+1.59 V}] \overset{0}{Br}_2 ->[\pu{+1.07 V}] \overset{-1}{Br}^-}$$ I'm supposed ...
-2
votes
1answer
81 views

Electrolysis of molten sodium chloride [closed]

Can somebody explain me the electrolysis of molten $\ce{NaCl}$ via electrode potential? Reduction potential of $\ce{Cl-}$ is -1.36 V, while sodium metal is -2.76 V, but still sodium is reduced and ...
1
vote
0answers
42 views

Reducing agent in electrolysis [closed]

I would like to make colloidal silver to kill mold. I think $\pu{100ppm}$ (weight) would be nice. I read a paper on it and in it they used citric acid + distilled water as fluid, two silver plates as ...
1
vote
0answers
39 views

Calculate the potential of each electrode, $\ce{Mn(OH)2}/\ce{Mn}$ ox/red couple

So the exercise goes like this: We consider the chemical battery(i have no idea what is its actual english name since i'm translating), $\ce{Mn_{(s)}/Mn(OH)_2//Cu^{2+}/Cu_{(s)}}$ Where $\ce{Mn}$ is ...
2
votes
1answer
28 views

What is the equation for solving the concentration of the unknown from a Single-point Standard Addition Calibration for Potentiometry?

I know how to use the standard addition equation for a single-point analysis from an equation I got from the Analytical Chemistry book "Quantitative Chemical Analysis" 9ed by D. Harris. However, ...
0
votes
0answers
25 views

Why does half-reaction with largest positive potential will run as written while other is reversed?

While balancing the half redox reaction, the textbook indicated that the flip of equation is dependent on the size potential. But I do not understand the reason why it is like that. Please explain for ...
1
vote
1answer
81 views

How do you calculate a half cell potential Copper(II) and Copper Sulfate?

I have to complete an experiment for school where I have copper and zinc electrodes placed into an electrolyte of copper sulfate and I have measured the potential across it at varying temperatures. ...
0
votes
1answer
79 views

Which of the following reactions doesn't represent an oxidation-reduction [closed]

Which of the following reactions doesn't represent an oxidation-reduction? $$ \begin{align*} \ce{2 P + 5 HClO + 3 H2O &-> 2 H3PO4 + 5 HCl} \\ \ce{Zn + 2 HCl &-> ZnCl2 + H2}...
0
votes
0answers
23 views

How can I calculate for the theoritical potential needed to precipitate a metal in an electrolytic cell?

We were given a problem where we are to calculate the theoretical potential needed to initiate the deposition of $\ce{Cu^2+}$ in a solution buffered to $\mathrm{pH} = 4.00$ and the IR drop associated ...
0
votes
2answers
77 views

In a half cell reaction, Is the potential halfed?

If you have an electrolyte of $\ce{Zn^2+}$ and $\ce{SO4^2-}$ (Neutral) Then you dip in it a Zinc electrode. Zinc potential is $\pu{-0.74 V}$ (relative to SHE). So that means there is a $\pu{-0.74V}$ ...
1
vote
0answers
30 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: $$\ce{Sn^4+(aq) + Cu(s) -> Sn^2+(aq) + Cu^2+(aq)}$$ $$E^\circ_{cell} = \pu{-0.21 V}$$...
2
votes
0answers
43 views

Explain why can't zinc be plated out from a Zn(II) solution using standard reduction potentials

I am currently learning about electrochemistry using Zumdahl's Chemistry [1, pp. 709–710]. One of the critical thinking questions is Why can $\ce{Zn}$ not be plated out from an aqueous solution of $...
4
votes
1answer
102 views

Is the Standard hydrogen electrode potential at T other than 298 K also zero?

The standard hydrogen electrode potential by conventional at 298 K is taken to be 0.00 volts. This is what I have been taught. It talks about SHE at 298 K, so is the hydrogen electrode potential at a ...
-2
votes
2answers
80 views

What happens when two galvanic cells are placed in series

I understand how a single galvanic cell works, and the relation of equilibrium and the Nernst equation. But this appears to contradict the higher voltage in a series configuration because it ...
5
votes
2answers
107 views

Why is hypochlorite a stronger oxidizing agent than other oxychlorides?

The reduction potentials of perchlorate, chlorate, chlorous acid and chlorine dioxide in acidic and basic solutions are listed in the table below: $$ \begin{array}{lcc} \hline \text{Oxychloride} & ...
-1
votes
1answer
38 views

Would this experiment be electrolysis experiment be viable?

I plan to do a 'research project' or an experiment involving the electrolysis of dilute sulfuric acid. The idea or 'question' is this: Would there be a variation in the $\mathrm{pH}$ of the ...
0
votes
1answer
32 views

Fuel cell potential for the electrolysis of ammonia

I am trying to calculate the fuel cell potential for the electrolysis of ammonia with the following equation: ...
0
votes
0answers
29 views

Reaction between copper and silver(I) nitrate in aqueous medium

What is the reaction between $\ce{Cu}$ and $\ce{AgNO3}$ taking place in aqueous medium? The answer given was: "Only" oxidation of $\ce{Cu}.$ My concern is: how is only oxidation of $\ce{Cu}$ ...
1
vote
1answer
242 views

Electrode potential for metal-metal ion and metal-metal insoluble salt-salt ion electrode

So I read it in a book that The potential of metal-metal ion electrode and metal-metal insoluble salt-salt anion electrode is same while their standard potentials are not same. Standard potential ...
0
votes
0answers
25 views

Electric potential of a redox reaction (without solids)

I need someone to help me with a problem: We have a solution which is $\pu{0.1 M}$ of $\ce{KMnO4}$ and $\pu{0.1 M}$ $\ce{Fe^2+}$ and has $\mathrm{pH}=0$. Given the electrical reduction potential of ...
2
votes
1answer
88 views

Why do Cu⁺ ions spontaneously form copper metal and Cu²⁺ ions in solution?

The standard electrode potentials for three reactions involving copper and copper ions are: $$ \begin{align} \ce{Cu^2+(aq) + e- &-> Cu+(aq)} &\quad E &= \pu{+0.15 V} \\ \ce{Cu^2+(...
0
votes
0answers
57 views

Regarding Standard Electrode Potentials

If the standard hydrogen electrode (SHE) is set arbitrarily to have a potential that is equal to 0 V, and has an absolute real potential. Then, in electrochemistry, how are the electrode potentials of ...
4
votes
1answer
209 views

Electrolysis of water: Which equations to use? (IB Chem)

There is a list of standard electrode potentials at 298 K from the p. 23 of IB Data Booklet 2016. Which of the following equations (forward/backward reactions), from the two possible ones involving ...
1
vote
2answers
97 views

Why is reduction potential of water ( 2H₂O + 2e⁻ → H₂ + 2OH⁻ ) is -0.83 insted of 0, as in the case of (2H⁺ → H₂)?

I came across this value of reduction potential of water while solving a question. Also, I noticed that, for example $$\ce{Ag+ → Ag}$$ has a fixed standard potential, and the same is used when we do ...
2
votes
2answers
111 views

Oxidation of metals/halogens by oxygen gas in acidic aqueous solution

I had some confusion about the correct answer to the following question: Which substance can be oxidized by $\ce{O2(g)}$ in acidic aqueous solution? Two of the answer choices were metal cations (...
1
vote
1answer
399 views

[Co(H2O)6]3+ vs [Co(NH3)6]3+ oxidising water

Cobalt(III) complexes cannot be prepared by addition of the ligand to a solution of the metal cation because the aqua cation $\ce{[Co(H2O)6]^3+}$ has no stable existence in solution. It is strongly ...
1
vote
0answers
90 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+ -&...
0
votes
0answers
66 views

Why do reference electrodes have porous frits or membranes as a salt bridge?

From what I understand, they act as a salt bridge between the reference electrode electrolyte and the analyte solution (in a potentiometric titration). But why do we use partially permeable membranes ...
2
votes
1answer
77 views

How does a Pt and reference electrode measure the cell potential in a potentiometric titration?

I'm trying to perform a potentiometric titration to determine the redox potential of a $\ce{Fe^3+|Fe^2+}$ couple. To do this, I am using an $\ce{Ag|AgCl}$ electrode connected to an inert $\ce{Pt}$ ...
1
vote
1answer
19 views

Can a half-reaction be oxidation if it has the higher reduction potential?

I am working on a problem that provides these two half-reactions: $$ \begin{align} \ce{Fe^3+ (aq) + e- &-> Fe^2+ (aq)} &\quad E^\circ_\mathrm{red} &= \pu{+0.77 V}\\ \ce{S2O6^2- (aq) + ...
2
votes
0answers
491 views

OF2 vs O2F2 oxidising strength

My teacher said that OF2 is the third most powerful oxidising agent after F2 and atomic O, but I think O2F2 should be even more oxidising, since it less stable than OF2. I just read on quora that O2F2 ...
3
votes
1answer
77 views

Compound having highest standard reduction potential

Which compound has highest SRP (standard reduction potential) value, e.g. the strongest oxidising agent? In most tables $\ce{F2}$ is at top with $E^\circ = \pu{2.87 V}$, but I've found a table listing ...
-1
votes
1answer
54 views

Standard electrode potential

What is meant by the following: Electrode potential for $\ce{M^3+/M}$ Is it standard oxidation potential (SOP) or reduction potential (SRP)? What does a high positive or negative value for SRP and ...
1
vote
1answer
176 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 ...
0
votes
1answer
147 views

How to predict ease of oxidation or reduction for a given oxidising or reducing agent? [closed]

I have never understood which agent will be able to oxidize or reduce which type of reactants and yield which type of products will be formed. For example I want to know about DIBAL-H and how is it ...
3
votes
2answers
162 views

Proof of the chemical potential formula

My textbook as well as Wikipedia both state the formula $\mu_A = \mu_A^0 + RT\ln\{A\}$ which gives the chemical potential $\mu_A$ of a chemical species $A$ as function of the standard chemical ...
2
votes
0answers
51 views

Can hydrogen plasma reduce carbon dioxide?

There are several studies describing usage of hydrogen plasma to reduce metal oxides. This is not yet widely adopted in industry, but it is of interest for environmental reasons (such as desrcibed in ...
-1
votes
1answer
133 views

Calculating cell-potentials

I have measured the cell potential between a number of metals e.g. Ni, Pb, Al, Cu and Zn by constructing a galvanic cell and then used a voltmeter to measure the potential. Now, if I want to ...
1
vote
1answer
266 views

Why do potassium, rubidium, cesium all have lower standard potentials than sodium?

Why do potassium, rubidium, cesium all have lower standard potentials than sodium? Sodium has a higher charge density than any of them, so its enthalpy of hydration should be larger, right? The ...
0
votes
1answer
2k views

Changing Temperature of a Galvanic/Voltaic Cell: Should I wait for the electrodes to also change in temperature?

I'm conducting an experiment where I change the temperature of the sulfuric acid in a lead acid storage cell. My one question in controlling the variables is that should I let the electrodes also ...
-1
votes
1answer
305 views

Galvanic/Voltaic Cell: Does Cell Voltage Change When A Resistor Is Connected?

I tried making a lead acid battery. After charging for about 10 minutes, I connect the voltmeter in parallel to the cell and see that there is around a 1.2V (which is quite lower than what I predicted)...
0
votes
1answer
55 views

Does silver oxidise in a pH 1 solution?

Consider submerging a plate of pure silver in a solution with $\mathrm{pH} = 1$. Does the redox reaction with hydrogen happen spontaneously? The composition of the solution is not given. My ...
0
votes
2answers
282 views

Lead-Acid Battery: Standard Electrode Potential

I'm making a lead-acid battery for an investigation. Since I only had sulfuric acid and lead electrodes, I decided to firstly run 2 lead electrodes through electrolysis in a sulfuric acid electrolyte. ...
1
vote
0answers
26 views

Potentiometric determination of fluoride

We did an experiment of potentiometric determination of fluoride ions. In several beakers we added several concentrations of NaF solutions and then we added water. We calculated with the electrode the ...
5
votes
1answer
286 views

Will nitrate be able to oxidise mercury?

We have the following data: \begin{align} \ce{NO3- + 3 e- &-> NO} &\quad E^\circ_1 &= \pu{0.96 V}\\ \ce{Hg^2+ + 2 e- &-> Hg} &\quad E^\circ_2 &= \pu{0.86 V} \end{align} ...
1
vote
0answers
269 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 ...