All Questions
Tagged with equilibrium redox
33
questions
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Single electrode potential measurement
My textbook says that in a galvanic cell, it's not possible to measure single electrode potential independently. Instead, a Standard Hydrogen Electrode is used as the system is under equilibrium. Can ...
4
votes
2
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804
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Acid dissociation constant from conductometric data
$\ce{0.007 M}$ aq. solution of anilinium hydrochloride had molar conductivity equal to $\pu{119.4 S cm2 mol-1}$, which became $\pu{103 S cm2 mol-1}$ when a few drops of aniline were added to the ...
2
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3
answers
2k
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Why is the voltage produced by a voltaic cell affected by temperature as described by the Nernst Equation?
I understand why changing the concentrations of the electrolytes in a voltaic cell affects the voltage. Given a zinc-copper cell for example, if I were to increase the concentration of the zinc ...
-3
votes
1
answer
148
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Side reaction of I− and acidity of HI
In acidic conditions, I− tends to get oxidised by atmospheric oxygen to give iodine. This is evident in iodine based titration, where upon leaving the setup, blue colour of starch reappears as iodine ...
1
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1
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768
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Why is the theoretical value of the electrode potential different to the experimental value for Cu and Al for a galvanic cell by using Nernst equation
I've construct a galvanic cell with the Al strip putting in the Aluminum nitrate solution and Cu strip putting in the CuSO4 solution. KNO3 is used as the salt bridge in this experiment. The question ...
0
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49
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Concentration of solution when a battery reaches equilibrium
Problem: We want to build a battery employing as electrodes ${\text{PbSO}_4}_{(s)} | {\text{Pb}}_{(s)}\ (E^º=-0.351\ V)$ i ${\text{Cd}}_{(aq)}^{2+} | {\text{Cd}}_{(s)}\ (E^º=-0.4026\ V)$ in a solution ...
4
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1
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120
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Redox titration, complex formation effect on lg'K?
We have performed the following redox titration
(1): $\ce{MnO_4^- + 8H^+ + 5Fe^2+ <=> Mn^2+ + 4H_2O + 5Fe^3+}$
where we have used a iron(II)solution (the analyte) and titrated it with a ...
-3
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1
answer
71
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Voltaic cell equilibrium confusion
In a voltaic cell, taking one with $\ce{Zn}$ and $\ce{Cu }$ electrodes for an example, an EMF is formed because the equilibria at the $\ce{Zn}$ electrode is shifted more towards the $\ce{Zn^2+ + 2e-}$ ...
1
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2
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338
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Effect of H+ concentration on equilibria
Considering the two equilibriums below, when the $[\ce{H+}]$ decreases, my book says that equilibrium \eqref{rxn:2} will shift to the left by a greater extent compared to equilibrium \eqref{rxn:1} ...
0
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1
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170
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Calculating Gibbs free energy change when the state of ions is unknown
Problem
Calculate $\Delta G^\circ$ for the following reaction:
$$\ce{Zn(s) + Ag2O(s) + H2O(l) -> Zn^{+2}(aq) + 2Ag(s) + 2OH-(aq)}$$
Given $E^\circ_{\ce{Ag+/Ag}} = \pu{0.80 V}$, $E^\circ_{\ce{Zn^{+...
2
votes
0
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41
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Do decomposition potentials change during electrolysis?
I was just wondering if decomposition potentials actually change during electrolysis. For example, if we reversed the Daniell cell reaction so that copper is oxidized, the half cell reactions would be:...
2
votes
1
answer
318
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Relation between standard silver-silver chloride electrode potential and solubility product of silver chloride
I learned that $E^\circ_\ce{Cl^-|Ag,AgCl}, E^\circ_\ce{Ag^+|Ag}$ and $K_\mathrm{sp}$ of $\ce{AgCl}$ are related as
$$\boxed{E^\circ_\ce{Cl^-|Ag,AgCl} = E^\circ_\ce{Ag^+|Ag} + \frac{RT}{F}\ln K_\mathrm{...
1
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0
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702
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Sodium hydroxide reaction with manganese dioxide [duplicate]
I came across a website that said it is possible for sodium hydroxide to react with manganese dioxide at temperatures near 0 degrees Celsius. The reaction goes:
2MnO2 + 3NaOH ⇄ MnO(OH) + Na3MnO4 + H2O
...
1
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1
answer
221
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Why is "activity" of gaseous component equal to its partial pressure but that of aqueous component its concentration?
While solving an electrochemistry problem I had to calculate the reaction quotient of this reaction:
$$\ce{2Fe(s) + 4H+(aq) + O2(g) -> 2Fe^{2+} (aq) + 2H2O (l)}$$
It turns out to be: $$\ce{Q=\dfrac{...
1
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0
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174
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Understanding Pourbaix diagram
I am recently taking courses in environmental chemistry and I was introduced to Pourbaix diagram. I was taught that the lines in the Pourbaix diagrams are equilibrium lines. Lets take as an example ...