Redox is the portmanteau of reduction and oxidation and therefore refers to reactions in which electrons are transferred and in consequence the oxidation state of the involved elements changes.

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Plotting ΔG vs Temp for Electrochemical Reaction

I’m doing an electrochemistry lab that requires me to construct various galvanic cells in an attempt to solve for $\Delta H$, $\Delta G$, and $\Delta S$ values of an unknown. During one part of the ...
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How to determine the value for n in the Gibbs free energy and redox potential equation?

I am having a problem with this equation for redox potentials $$\Delta G=-nF\Delta E$$ In this equation I never am totally sure about what the value of $n$ should be, for example for the reaction ...
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Why does a reduced compound become a better electron donor?

When a compound gains an electron, why are they more likely to give them up (i.e. become stronger reducing agents)?
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Zinc in acidic permanganate solution?

How can this be described by redox equation? My attempt: Half reaction as follows: Then overall reaction:
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How can I balance the following equation atomically and electrically?

$$\ce{C2O4^2- + MnO2 -> Mn^2+ + CO2}$$ I think that the half reactions are $$\ce{C2O4^2- -> CO2}$$ $$\ce{MnO2 -> Mn^2+}$$ I am supposed to balance these by adding water, $\ce{H+}$ atoms ...
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If losing electrons means getting oxidized, then does it mean that ALL metals are reducing agents, since they themselves get oxidized?

I was just going through my last year's school textbooks and while I was reading this chapter on Redox, this above question crossed my mind. Shouldn't it be true that since ALL metals lose electrons ...
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Fluorination with xenon difluoride

Is this an error? Why is the nitro group reduced as the benzene ring is oxidized? I don't see any possible reducing agents here.. Also, what is the mechanism of aromatic fluorination by xenon ...
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What is the byproduct from hydrogenolysis of an acyl chloride?

What's the byproduct of this reaction? After all, it is a "lysis" reaction. So ... would HCl be a byproduct?
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Balancing Redox Equations - Half Reactions

How do I balance this using the half-reaction method: $$\ce{Zn(s) + HCl(aq) -> Zn^{2+} (aq) + H_2 (g)}$$ I would first split it up in its ionic components: $\ce{Zn(s) + H^+ + Cl^- -> Zn^{2+} ...
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How much ozone is produced by ionization of air and how turn ozone into oxygen

I want to make a plasma speaker. I'm worried about the amount of ozone being produced by the ionization of the air and it possibly not being a safe amount. Even if it doesn't produce a dangerous ...
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Corrosion of iron

First question regarding corrosion of iron: Why is anodic area always located at nicks and scratches, where energy state is high? (does"high [potential] energy" mean unstable structure?) ...
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Does hydrogen react with air at room temperature and pressure?

I have a container with 3% hydrogen and the rest is air. How fast the hydrogen will get oxidized by air? How much the reaction will speed up with increased temperature? Thanks so much.
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While electrolyzing concentrated aqueous sodium chloride, why is it that chlorine is discharged but not sodium?

Hydrogen and hydroxide both exceed sodium and chlorine in terms of reduction and oxidation potential respectively. While electrolyzing a concentrated solution of aqueous NaCl, it is known that ...
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Concentration cell lower half cell concentration from measured cell potential

I am trying to find the Ksp of silver thiocyanate: AgSCN(s) --> Ag+ (aq)SCN-(aq) but I need to first prove that the lower [Ag+] = 1.27-12 M, but don't know how to find it. The data I am given: ...
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47 views

Frost diagram and acidic/basic conditions.

The Frost diagram for sulfur shows the relative stability (in terms of cell potentials) of the possible aqueous oxidation states. What is the reason for the instability of higher oxidation states in ...
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38 views

Does this equation balance?

$$\ce{CaCO3 + 2H2O + Pb^{2+} -> Pb(CO3) + Ca(OH)2 + H2}$$ Does this equation balance? On the right you have lead with 2+ charge, whereas on the right its completely neutral. So my question is do ...
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90 views

Strongest oxidizing agents and reducing agent

I have to find out the strongest oxidizing agent and the strongest reducing agent in: $\ce{Cr(NO3)2(aq)}$ and $\ce{FeCl3(aq)}$. This is my current thinking: $\ce{Cr(NO3)2(aq)}$ Contains ...
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Why does the OAc group leave in the first step of Oxymercuration?

The above picture shows the first step of Oxymercuration. The electrons attack the Mercury atom but the OAc group leaves. Why is this? Hg is a transition metal with a number of available oxidation ...
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How do I go about balancing these equations?

I have to use oxidization number approach. $\ce{Co^2+ (aq) + H2SO3(aq) -> Co^3+(aq) + S2O3^2- (aq)}$ This is my approach so far: The change in Co is 1 electron, the change is S is 2 electrons, ...
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26 views

Ionize Hydrogen and Oxygen Gas in Electrolytic Cell?

As is well known, water can be electrolyzed into oxygen and hydrogen gasses. However, all redox reactions can be run in reverse. If I were to electrolyze water in 2 closed containers (in order to trap ...
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28 views

Is reduction potential equivalent to the ease of discharge?

Loosely speaking, is the reduction potential equivalent to the ease of discharge in the context of electrolysis? i.e. is it easier to discharge an ion with a higher reduction potential as opposed to ...
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CO detector reaction

I have recently bought a CO spot detector which is not working the way I intended for it. A CO spot detector is a analog carbon-monoxide detecting patch that changes color when it comes in contact ...
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Why do the pennies in the pre/post 1982 penny experiment sometimes dissolve completely?

USA pennies were nearly pure copper pre-1982. Post 1982 they are copper clad zinc. A common experiment in US high schools is to notch pennies with a file and add them to an HCl solution. The old ...
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283 views

Balancing a REDOX reaction using the oxidation number method, in acidic solution

I am trying to balance the REDOX equation shown below, but I got stuck after balancing the major atoms. Where can I go from here? I know I need to balance the H and O atoms, and make sure the charges ...
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Balancing REDOX reactions in a basic solution, when no H+ ions are present

I am trying to balance the following redox reaction, in basic solution. From what I have learned, to balance a redox reaction in basic solution you simply balance it as you normally would in acidic ...
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Oxidation and reduction [closed]

Separate this redox reaction into its component half-reactions. $$\ce{2K + Cl2 -> 2KCl }$$ Oxidation half-reaction: Reduction half-reaction. Use the e- for an electron
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Aluminum deoxidation gas

I am new to chemistry. I am looking for a gas that would de-oxidise aluminium. Which gases would work for that and at what temperature? Details: I need to sinter aluminium powder. But because the ...
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Reaction balance

I got this redox reaction on my exam that I didn't know how to balance. $$Sodium~iodate+sulphur~dioxide+water\ce{->}sodium~sulphate+sulphuric~acid+iodine$$, thus it would be: $$\ce{NaIO3 +SO2 ...
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256 views

Why does temperature affect cell potential?

The Nernst equation describes the relationship between cell potential and temperature. But why does temperature affect cell potential? My understanding is that the collision model of kinetics is not ...
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Hydrogen fuel cell - why do the H+ ions move through the electrolyte

Consider the following hydrogen fuel cell http://butane.chem.uiuc.edu/pshapley/Enlist/Labs/FuelCellLab/FuelCell.html At the anode, hydrogen is oxidised (losing electrons). My first question is ...
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325 views

Ionic equation for reaction of iron (ii) chloride and zinc?

I know that the zinc half equation would be $\ce{Zn -> Zn^{2+} + 2e}$ However I am confused about the half equation for iron. I would think that since iron is completely displaced, it's oxidation ...
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251 views

Ionic equation for reaction of potassium permanganate with potassium iodide?

The half equation for the reduction of the permanganate would be $$\ce{5e- + 8H+ + MnO4- \rightarrow Mn^2+ + 4H2O}$$ But with regards to the iodide, I am very confused. I have seen some sources say ...
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409 views

Green Potassium Manganate and Sodium Hydroxide Equation

When a sample of green potassium manganate (VI), $\ce{K2MnO4}$, is added to aqueous sodium hydroxide, a brown black solid A and a purple solution of B are obtained. I know that the brown black solid ...
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How has Iodine gained electrons?

Two chromium atoms gain 3 electrons each. They go from 0 to 3+ Similarily, 6 iodine atoms go from -1 to 0, thus gaining one electron. However my textbook says that Iodine has lost electrons. How? ...
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Reduction of amides

The reduction of an amide using LAH yields a primary amine . I looked up the mechanism over here. The mechanism suggests that the final main product (amine) is produced before giving the products a ...
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What property of zinc chromate makes it a good anticorrosion paint

What properties of zinc chromate make it a good anticorrosion paint? I know that stainless steel is protected by a layer of chromium oxide. Is it because the zinc chromate doesn't flake off the ...
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55 views

How does zinc become oxidized when it's not in direct contact with copper ions in a galvanic cell?

Whenever a galvanic cell is explained in textbooks/videos, it usually starts by showing that if you put a piece of $\ce{Zn}$ in a $\ce{Cu^{2+}}$ ion solution, the $\ce{Zn}$ will become oxidized and ...
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n-factor for ammonium nitrite?

The given reaction is $$\ce{NH4NO2 \rightarrow N2 + 2H2O}$$ The way I did it was $$\ce{NH4+ \rightarrow \frac{1}{2} N2 + 4H+ + 3e-}$$ and $$\ce{NO2- +3e- +4H+ \rightarrow \frac{1}{2} N2 + 2H2O}$$ ...
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Why is water considered ionic in fuel cells but otherwise covalent?

If water, $\ce{H2O}$ is a covalent compound formed by sharing of electrons, why is it said (in case of fuel cells) that formation of water from hydrogen and oxygen is a redox reaction (transfer of ...
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Redox reaction with tin and sulfuric acid solution

I need to write the redox reaction from tin and a sulfuric acid solution. Here is the solution: The first half-reaction: $\text{Sn}\rightarrow \text{Sn}^{2+}+2\text{ e}^-$ The second ...
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Does NaOH react with K to form NaOK or KOH?

I realized that the $\ce{-OH}$ group when it reacts with some metal like $\ce{Na}$ or $\ce{K}$ will replace the $\ce{H}$ element to form $\ce{-OK}$ or $\ce{-ONa}$: \begin{align} \ce{H2O + Na ...
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Why reduced atoms are more energetic?

For example, in glycolysis, $\ce{NAD+} $ is reduced to $\ce{NADH}$ and then it's more energetic. Why adding electrons to an atoms gives it more energy?
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The anode and cathode when corrosion happens

Let's say $\ce{Fe}$ reacts with $\ce{Cu^{2+}}$ ions. $\ce{Fe}$ would oxidize and therefore give electrons to $\ce{Cu^{2+}}$so that: $$\ce{Fe-> Fe^{2+} +2e-}$$ $$\ce{Cu^{2+} +2e^- ->Cu}$$ The ...
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Redox Half Reaction - Reduction

I can't seem to figure out this redox reaction. Is the charge on the Carbon in the $\ce{CO2}$ supposed to match the charge on the Carbon in the $\ce{CH3COO-}$? I am supposed to build a half ...
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Hydrazine as a reduction agent

When using hydrazine as a reduction agent to reduce graphene oxide, which is the product hydrazine oxidises to?
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Relationship between surface area of electrode and reaction rate of hydrogen in fuel cells

I am looking at the effects of increasing the surface area of which the flowing hydrogen fuel is in contact with the anode in a fuel cell. At the anode the hydrogen is catalytically split into ...
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What is actually a redox reaction?

I need to know what a redox reaction is. How could a redox reaction possibly be identified? Also, I have a confusion whether, $$\ce{H -> H+ + e-}$$ $$\ce{e- + Cl -> Cl-}$$ $$\ce{H + Cl -> ...
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316 views

Principle of potentiometric titration

In potentiometric titration between Ascorbic acid and Iodine when we plot the graph between EMF with volume of iodine consumed, we get a sudden decrease in emf at equivalance point,Why? It is also ...
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Sacrificial Anodes and Pit Corrosion

I have a slab of aluminum and one part of the slab will be exposed to a very corrosive environment. If I put a sacrificial anode elsewhere on the slab will the section that is exposed still be ...
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Why should the redox reaction happen between the copper ions and iron atoms?

I know that when $Cu$$^+$$^2$ ions react to $Fe$ atoms, it becomes $Cu$ + $Fe$$^+$$^2$. My question is, why? Copper atoms normally have 29 electrons. These means that in the K-shell there are 2 ...