Questions tagged [redox]

Redox is the portmanteau of reduction and oxidation. This tag should be used in questions where both the reduction and the oxidation process are under focus. This tag is not limited to inorganic chemistry. If the question is specifically about either reduction or oxidation (not both) of an organic compound, use [organic-reduction] or [organic-oxidation] instead.

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Questions concerning redox reactions [closed]

What does it mean for an element to be reduced? What does it mean for an element to be oxidized? What is an oxidizing agent? What is a reducing agent? How do you identify oxidizing and reducing ...
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Confused with oxidation numbers

If -2 is a oxidation number and 2- is the charge, then what is - by itself, is it a oxidation number or charge? As in $\ce{Ag+}$. Also do you see $\ce{Cu + 2Ag+ -> Cu^{2+} + 2Ag}$ as a redox ...
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Vycor + hydrogen at 750°C - reduction? [closed]

Does anybody have experience with Vycor 96% silica tubing in hydrogen at bright red heat, around 750°C, regarding its reduction to silicon monoxide or elemental silicon?
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What is the oxidizing agent for Fe in the following redox reaction?

Redox: $\ce{Fe + 2HCl -> FeCl2 + H2}$ Oxidation: $\ce{Fe -> Fe^{2+} + 2e-}$ Reduction: $\ce{2H+ + 2e- -> H2}$ The $\ce{HCl}$ and $\ce{H2}$ are formed by covalent bonds. The $\ce{FeCl2}$ ...
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Which two substances react spontaneously?

Which two substances react spontaneously? (A) $\ce{Ag}$ and $\ce{Cu}$ (B) $\ce{Ag+}$ and $\ce{Cu}$ (C) $\ce{Ag}$ and $\ce{Cu^2+}$ (D) $\ce{Ag+}$ and $\ce{Cu^2+}$ $\tiny{\...
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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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what are reduction oxidation reactions?

in the picture, the product is a neutral material, but in the illustration of the molecular structure, the compound is shown in its ions, why we can't show it in its ions even in the equation or if we ...
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Would it be possible to produce a non-toxic atmosphere using a coal fire and frozen oxygen?

A Pail of Air is a classic science fiction short story by Fritz Leiber from 1951 describing how a family survives on an Earth that has left its orbit around the sun, using desparate low-tech methods: ...
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How does iron rust in basic conditions?

I performed an experiment about the corrosion of iron. I used acid and base in the experiment. I understand that the acid speeds up the corrosion of iron. But I don't understand why the base also ...
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Can bromide ion reduce ferric ion?

Can bromide ion reduce ferric ion ? Just a query. In my opinion it can since bromide ion can undergo oxidation. Is my answer correct?
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Why are more easily oxidized elements more reactive than less easily oxidized elements?

Why do the more easily oxidized elements displace the less easily oxidized elements? Question inspired by Activity Series of Metals
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Explaining redox reactions to a 6 year old?

In a similar vein and for pretty much the same reason as I post this question on the Physics.SE site, what would be a an effective means to promote understanding about redox reactions to a 6 year old? ...
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Electrolysis Anode equation

In the electrolysis of $\ce{Na2SO4}$, is it valid to write the anode half-reaction (oxidation) as $$ \ce{OH-} \rightarrow \ce{H+} + \frac{1}{2}\ce{O2} + 2\ce{e-} $$? My book says it's $$ \ce{H2O} \...
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Why is it hard to reduce titanium dioxide?

Titanium is expensive, although it is not rare and titanium dioxide is a ubiquitous component, it's part of such mundane articles as toothpaste, paper or plastics. The reason for that is that the ...
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Are these two reactions equivalent?

I'm supposed to balance a redox equation. I arrive at $$ \ce{H2O} + \ce{NH4+} + 2\ce{S^{2-}} + \ce{O2} \rightarrow \ce{NH3} + 2\ce{S} + 3\ce{OH-} $$ The "official" solution is $$ 4 \ce{NH4+} + 2\ce{...
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Can a battery powered by iron and air really provide a feasible power source for automobiles?

I'm referring to the Shuttle Battery recently announced (read more on it here) that suggests that: The energy density of the device is up to 7,700 Wh/L. It is more than 5 times higher than state-...
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Is it true that iron (Fe 0+) cannot exist when there's water around?

So somebody told me that iron metal (zero charge) cannot exist at all when $\ce{H2O}$ is present because it will all turn into rust. How is this possible? Isn't there some sort of equilibrium? Does it ...
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Why does Chloride attack CrO?

In certain applications some sorts of stainless steel (V2A, 1.4301) corrode when exposed to $\small{\ce{Cl^-}}$ in water, or at least it is strongly advised to use ...
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Vertical lines in a Pourbaix Diagram

I know that because of the absence of the hydrogen ions in a reaction ($n_{H+} = 0 $) , the correspondent E-ph line have to be horizental , but what exactly the types of reactions (if there is) that ...
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Balancing redox reaction with one reactant

Consider the following acidic reaction: $\ce{As -> H2AsO4- + AsH3}$ How would I go about balancing this using the half reaction/ion-electron method?
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What's the technical term for supercharging an acid with an oxidizer? And does it always work?

In a recent Mythbusters episode, where they tested some Breaking Bad chemistry assertions, they debunked the hydrofluoric acid body-dissolving myth referenced elsewhere in Chemistry.SE in the question ...
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Is there an alternative to the half-reaction method to solving red-ox reactions?

The equation for the reaction between a permanganate and iron(II) ions in acidic solution is: $\text{MnO}_4^- + \text{Fe}^{2+} \longrightarrow \text{Fe}^{3+} + \text{Mn}^{2+}$ My book, as well as a ...
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Electrode potentials at interfaces?

My questions relates to the fundamental concept of electrochemistry, more specifically the electrode potentials. 1) First, why is there a potential difference at the interface of two phases? ...
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Reaction of an electrode

Why is the cathodic reaction of $I^-/AgI/Ag$ is $$\ce{AgI + e- -> Ag + I-}$$ but not, $$\ce{Ag+ + e- -> Ag }$$ whereas, in $Ag/AgCl(s)$, $KCl$(0.2M); it is $$\ce{Ag+ + e- -> Ag}$$
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Electrochemical Cell

Now in an electrochemical cell , we make use of the fact that whenever there is a potential drop , electrons will flow from lower to higher potential as for a potential drop , there must be an ...
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Reduction by thermionic electrons

Certain reduction reactions require electrons as reducing agents. Is the overlapping of orbitals is necessary for electron transfer? I mean if a element $\ce{X}$ is heated and it gives out thermionic ...
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What is an oxidizer?

When talking about gaseous fuel / oxidizer mixture what does one mean by oxidizer if there is no oxygen involved? Is it correct to think of oxidizer as the more electronegative specie, because it is ...
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If a sugar is nonreducing, does that mean it doesn't ionize in water?

I'm thinking of sucrose, which I learned is nonreducing, what I take to mean it doesn't accept/take electrons from the surrounding solution. Does this also mean that it doesn't ionize and thus has a ...
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Are redox half-reactions “real”?

Are the half-reactions used in analyzing redox reactions a real thing or are they a conceptual shortcut? Is there a way to, however briefly, run a half-reaction by itself without the corresponding ...
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How does hot tub “shock” work?

Hot tub shock is potassium peroxymonosulfate. When added to a hot tub, it creates bubbles. It is said to oxidize organic debris in the water. What is the reaction?
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Why is mercury a “fancy proton”?

I remember that one of my old organic chemistry profs referred to mercury as being a "fancy proton". I think it was in the context of oxymercuration reduction. What might have been his rationale for ...
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What is the timescale of disulfide bond formation?

What is the timescale of disulfide bond formation in a given protein? What influences it? Finally, how does one actually measure it? From what I understand, the reduction and oxidation of bonds ...