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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Reactions involved in Titanium Anodisation

I am writing up a lab report investigating titanium anodisation and producing oxide layers. After some searching, all I can find is the reaction $\ce{Ti + O2 \to TiO2}$, which I am having no trouble ...
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25 views

What is the standard potential of carbon?

What's the value of standard potential of carbon? The hydrogen and Carbon are in the electrochemical series despite being non metals hydrogen has zero potential difference what about carbon?
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28 views

According to this equation for glycolysis, what is reduced and where do the electrons go?

I know that the glucose is oxidized into pyruvate but I don't understand what is reduced or where the electrons go.... Equation: $\ce{Glucose + 2 ADP + 2 NAD^+ -> 2 Pyruvate + 2 ATP + 2 NADH}$
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189 views

How many hydride ions are available in NaBH4?

Different sources have different answers. In the reduction of an aldehyde or ketone to an alcohol by Sodium Borohydride, how many moles of aldehyde are reduced by one mole of Sodium Borohydride? ...
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52 views

Are aqueous solutions of oxidizing agents safe?

In the "reducing agent" article in Wikipedia it says Good reducing agents are reagents that deliver $\ce{H2}$. Wouldn't that make water unsafe to dissolve oxidizing agents?
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60 views

How to identify which of two given electrodes with corresponding solutions is reducing more?

For the sake of the question, let’s assume that you are provided with two labelled rods of the pure metals $\ce{A}$ and $\ce{B}$ and two unlabelled bottles containing $1.0\ \mathrm{mol\ dm^{-3}}$ ...
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82 views

Can the thermodynamic predictions of redox reactions based on E and dG contradict each other?

I am referring to the following three reactions. Two of these reactions are imaginary ($\ce{M}$ and $\ce{X}$ are imaginary). $$\begin{alignat}{3} \ce{X- + 2e- \;&<=> X^3-} \qquad ...
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48 views

For the half reaction HSO3- -> S2O6^2- why is it that 2e- are on the right hand side when balancing and not one electron?

$$\ce{HSO3- -> S2O6^2-}$$ The oxidation number of $\ce{S}$ on the left is +4 and +5 so when adding electrons to balance the oxidation number why is $\ce{2e-}$ added to the right instead of one? ...
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190 views

Why is CaO + SO2 --> CaSO3 not a combination redox reaction?

I understand that a combination reaction is one where two substances combine to form a third substance, like with $\ce{2Na + Cl2 -> 2NaCl}$ but I do not understand why $\ce{CaO + SO2 -> CaSO3}$ ...
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28 views

Reduction of vanadyl ion

I want to reduce vanadyl to vanadium (III), can somebody please suggest some appropriate methods for it? I am trying to make a redox flow battery for a project but I have only vanadyl sulfate.
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31 views

Respect to other chemicals in reduction/oxidation potentials

From what I understand, the standard reduction/oxidation potential table is based on the hydrogen half reaction which makes a reduction and oxidation potential of 0 respectfully. In a research ...
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55 views

Pourbaix diagram – writing reactions

How would you go about writing the reaction between water and chromium metal under standard acid and base conditions? I know you would have to look at the vertical lines at pH 0 and 14 but I don’t ...
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51 views

Why does LiAlH(O-tert-Bu)3 not reduce acyl chlorides to alcohols?

Why do $\ce{LiAlH(O-^{t}Bu)3}$ and similar bulky reducing agents not reduce acidic chlorine further? $$\ce{CH3-COCl + LiAlH4 + H2O -> CH3-CH=O -> CH3-CH2-OH},$$ but $$\ce{CH3-COCl + ...
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45 views

If given a half reaction, how do you determine if an element can exist in a acidic conditions?

I was given the formulas, $$\begin{alignat}{2} \ce{MnO4^2- \;&<=> MnO4- + e-}\quad &&E^\circ = -0.56\ \mathrm{V}\\ \ce{MnO2 + 2H2O \;&<=> MnO4^2- + 4H+ + 2e-}\quad ...
4
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26 views

Galvanic reaction between aluminum and carbon fiber composite

I understand that there is a galvanic reaction between aluminum and carbon fiber composite. Structural aluminum parts in contact with carbon fiber composites should be insulated by something like ...
4
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1answer
32 views

Electroless Plating of Zinc onto Copper in NaOH Solution

I’m researching how the classic “alchemy” demonstration works in which zinc is plated onto a copper penny in a solution of sodium hydroxide. Most online resources refer to the electroplating of copper ...
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1answer
37 views

Balancing reduction equations for galvanic cell

Problem: Compute the potential of the following galvanic cell: $$(\ce{Mg (s)} \mid \ce{Mg^2+ (aq)}\ (0.30\ \mathrm{M}) \mid \mid \ce{Sn(OH)4^2- (aq)}\ (0.10\ \mathrm{M}); \mathrm{pH} = 9 \mid \ce{Sn ...
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46 views

Why is in the reaction of cyclic unsaturated aldehydes with hydrazine and hydrogen peroxide the aldehyde preserved?

What is the product of this reaction, which I found in our high school textbook? At first, I thought this was a typical Wolff-Kishner reduction, but then I saw the reagents didn't match up (no ...
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79 views

Dissolving metal reductions

Could reduction of an organic compound by reacting it with sodium dissolved in $\ce{NH3}$ still proceed if a metal such as aluminium were used instead of sodium? I'm not sure about the aluminium amine ...
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1answer
52 views

Disproportionation with aqueous NaOH

Which of the following undergoes disproportionation with $\ce{NaOH}$? $\ce{SiO2}$ $\ce{CO2}$ $\ce{SO2}$ $\ce{SO3}$ $\ce{NO2}$ From the above we can conclude that $\ce{SiO2}$, $\ce{CO2}$ and ...
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What is the purpose of the solution in a galvanic cell?

In other words: What is the purpose of the solution that the electrodes are immersed in, in a galvanic cell, and is it possible to generate a current without any solution?
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34 views

Why does reduction always accompany oxidation and vice versa?

We've all learnt that the reduction always accompanies oxidation and vice versa Why is this so? Why is it not possible that a species releases an electron and the electron just "floats around"? Is ...
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63 views

Cathode gained mass in zinc electrolysis

I performed an electrolysis of zinc, using two zinc electrodes and a zinc nitrate solution. However, after leaving the electrolysis to run for 30 min, at about 0.4 A and 6 V, I discovered that the ...
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43 views

Reduction and oxidation in organic chemistry

What is the meaning of reduction and oxidation in organic chemistry? From what I learned in General chemistry - OIL RIG i.e oxidation is loss and reduction is gain (of electrons).But what do we say ...
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Is the following reaction redox? [closed]

Is the test of sulphur using sodium nitroprusside a redox reaction?
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What is formed when you leave iron (II) sulfate in plain air?

What is formed when you leave iron (II) sulfate in plain air? It was the question I found in textbook. Assuming that air is oxygen I solved it this way: $$\ce{FeSO4 + O2 -> Fe2O3 + SO2}$$ ...
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74 views

Purpose of ammine in Tollens' reagent

In this previous question the mechanism for the reaction of Tollens' reagent was outlined. As I understand it the oxidising agent in Tollens' is the diamminesilver(I) complex $\ce{[Ag(NH3)2]+}$ but ...
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75 views

Reaction of an organic compound with Reducing Agents

Suppose we have a chemical compound as : [Simplification of the structure : It is $\ce{-COOC_2H_5}$ bonded to a 5-carbon ring with one double bond and the ring is doubly bonded to $\ce{=O}$] ...
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62 views

Mercury into mercury oxide

How can I turn mercury metal into mercury oxide? I know that many metals will react with oxygen if enough heat is supplied in the presence of oxygen. If I heated up mercury enough and also supplied ...
2
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1answer
42 views

Single displacement reaction

Will sodium metal, if mixed well with iron oxide, displace the iron in a chemical reaction? I know thermite involves the mixture of aluminium powder and iron oxide, and the single displacement ...
2
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1answer
64 views

The hydrogen ion in acidified potassium manganate (VII)

Recently, I am playing with redox reaction and I come over a compound acidified potassium manganate (VII) ($\ce{KMnO4/H^+}$). I get confused that why they put $\ce{H^+}$ beside $\ce{KMnO4}$. Doesn't ...
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Why isn't dry CaCl₂ used to dry HCl gas instead of concentrated sulfuric acid?

In our chemistry books (like Concise Chemistry), it is given that concentrated sulphuric acid is used to dry $\ce{HCl}$ gas. But, concentrated sulphuric acid is a strong oxidising agent so, why isn't ...
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Stability constant for metal ion complex using reduction potential [closed]

Determine the stability constant of the zinc tetramine complex from the equations: \begin{align} \ce{[Zn(NH3)4]^2+ + 2e &-> Zn + 4NH3} & E(\text{red}) &= -1.04~\mathrm{V}\\ ...
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1answer
53 views

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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83 views

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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34 views

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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61 views

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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63 views

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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41 views

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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1answer
24 views

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?
3
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1answer
61 views

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+} ...
8
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349 views

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 ...
3
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1answer
84 views

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?
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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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67 views

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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89 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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79 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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103 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 ...