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].
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Why is Cr²⁺ is a good reducing agent but Mn³⁺ is a good oxidising agent? [duplicate]
The question is the same as the title states. In my textbook,[NCERT Chemistry I for Class 12 , pg no 217.] the following is written
$\ce{Cr^{2+}}$ gets converted to $\ce{Cr^{3+}}$ as the +3 oxidation ...
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Principle of potentiometric titration
In potentiometric titration between ascorbic acid and iodine, when we plot the graph of EMF with volume of iodine consumed, we get a sudden decrease in EMF at equivalance point--why? It is also ...
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Iodometric titration of copper – standard electrode potentials
Upon inspection of the standard electrode potentials for the half reactions for both $\ce{Cu^2+}$/$\ce{Cu+}$ and $\ce{I2}$/$\ce{2I-}$, it becomes apparent it should be the iodide ions that act as the ...
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What is the meaning of electrode potential?
When we say that the electrode potential for $\ce{Co}^2$$^+$/$\ce{Co}$ is -0.28 V and $\ce{Cu}^2$$^+$/$\ce{Cu}$ +0.337 V, what is the physical meaning?
Can you conceptually explain when two electrons ...
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392 views
Implicit dependence of reaction rate through reduction potential and activation energy
On one hand, the larger the reduction potential of a chemical reaction and the smaller its activation energy, the larger the reaction reaction. on the other hand the rate of a reaction depends on ...
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How to find the potential of a mixed Iron/ Cer solution?
Given the following half-reactions:
\begin{align}
\ce{Ce^{4+} + e^{−} &-> Ce^{3+}} & E° &= \pu{1.72 V}\\
\ce{Fe^{3+} + e^{−} &-> Fe^{2+}} & E° &= \pu{0.771 V}\\...
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The spontaneity of a redox reaction
Suppose we have a redox reaction and we want to see in what direction the reaction is spontaneous. We do this by comparing the standard reduction potentials of the sub-reactions available in the main ...
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On Spontaneity of the Redox Reactions
According to this Mc Graw-Hill link during a spontaneous redox reaction Gibbs Free Enthalpy must decrease and at the same time the change in the Gibbs Free Enthalpy is the maximum electric work that ...
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Why is standard reduction potential an intensive property?
My book says that
Since the number of electrons lost must equal the number gained, the half-reactions must be multiplied by integers as necessary to achieve the balanced equation. However, the ...
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352 views
Intuitive understanding of standard electrode potential
I have read many books on standard electrode potential and they define the term in various ways but I just can’t seem to get an intuitive idea of it.
$$\ce{Cu^2+ + 2e- <=> Cu}$$
Standard ...
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Why can we disregard stoichiometric coefficients when computing reduction potentials?
Example:
A $Cd // Cr$ Galvanic cell has redox half reactions:
$\ce{Cd^{2+} + 2e^- -> Cd}$
$E_{cell}$ = -0.4
$\ce{Cr^{3+} + 3e- -> Cr}$
$E_{cell}$ = -0.7
Balanced equation of reaction ...
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Derivation of relationship between Gibbs free energy and electrochemical cell potential
Why is $\Delta G = -nFE$?
I don't understand what the motivation is behind this definition. Was it derived or just given? The textbook provides no justification for this equation. In fact, much of ...
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Electrolysis of aqueous copper (II) nitrate
There are two copper blocks sitting in the $\ce{Cu(NO3)2 (aq)}$ solution, a battery is attached onto both of them, providing enough energy to start the reaction.
Since solid pieces of copper are ...
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Why do carbonates, oxides, and pure metals precipitate before metal sulfides?
Water tends to leach metals near the surface and deposit them deeper through precipitation in two layers. The upper layer is usually made of metal carbonates, oxides, and occasionally pure or native ...
