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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TiOSO4 Titration Test

I was on the lookout for research topics when I came across this article here. I got a little confused when it said, "The LiDBBQO2 intermediate reacts with another LiDBBQ complex to form Li2O2 in ...
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Thermal decomposition of metal nitrates: iron nitrate (II) and sodium nitrate - why the different products?

$$\ce{4Fe(NO3)2 -> 2Fe2O3 + 8NO2 + O2}$$ $$\ce{2NaNO3 -> 2NaNO2 + O2 }$$ Why do they decompose in different ways? Why do we get a nitrite with sodium but an oxide with iron?
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Does the rate of ion movment in a salt bridge affect the total voltage produced by a voltaic (Galvanic) Cell?

I was thinking that different salts used in a salt bridge in a voltaic cell may have different rates of flow (perhaps ionic radius or some other property effects the rate?) I was wondering, if some ...
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18 views

Would Al ions still be reducd to Al metal if it was aqueous soltion?

To my knowledge, Aluminium is mostly mined in the form of Aluminium oxide or Al2O3 and then the Bayer process is used to extract and refine the pure Aluminium. Now, The Al2O3 must be in a molten ...
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Molten NaI electrolysis

electrodes: Zinc electrodes electrolyte: molten sodium iodide I know that at the cathode, sodium metal will be formed because only sodium ions are present for reduction. At the anode, originally ...
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What is a good electrolyte?

During lab, we had been asked to add different metals to a ferroxyl indicator, such as zinc and magnesium. One of the questions is that the gel (ferroxyl indicator) contains good electrolytes such as ...
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Why do NaNO3 + Al + NaOH yield ammonia?

From Russian test problem 4301: $$\ce{3NaNO3 + 8Al + 5NaOH + 18H2O -> 8Na[Al(OH)4] + 3NH3(g)}$$ How does ammonia evolve here? Is it that we get hydrogen gas evolving in the reaction between Al ...
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Balancing the redox reaction Cl2 -> Cl^- + ClO3- by half-reactions

I am having some difficulty balancing the following reaction using the half-reaction method: $$\ce{Cl2(g) -> Cl^{-}(aq) + ClO3^{-}(aq)}$$ My attempt at the problem: By determining oxidation ...
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60 views

How do we get NaClO3 in the reaction between Cl2 and NaOH?

From problem no. 4080 in a Russian example exam set: $$\ce{6NaOH + 3Cl2 -> NaClO3 + 5NaCl + 3H2O}$$ How do we get that $\ce{NaClO3}$? I can't seem to guess. I found this explanation on YouTube, ...
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38 views

Efficient oxidation of KCl to KClO3

I am trying to convert $\ce{KCl}$ to $\ce{KClO3}$ through an efficient process. I realize that I could electrolyze a solution of $\ce{KCl}$ to obtain some $\ce{KClO3}$ as a precipitate, however this ...
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Efficiency of Electrochlorination

When using electricity to create sodium hypochlorite from a solution of water and dissolved Sodium Chloride. I see in most instances that a fairly concentrated solution of brine (10% or more) yields ...
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For alkali and lanthanide metals, is there a better liquid barrier to oxidation than mineral oil?

Most often mineral oil is used to store, protect reactive metals from oxidation. By far the best choice is to hermetically seal the metal in pure argon or some other inert gas, since, although mineral ...
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37 views

How would using Different Salts in a Salt Bridge Effect the Voltage Generated by Voltaic Cell?

If I use a range of different nitrate solutions (e.g. calcium nitrate, iron nitrate) for the salt bridge in a voltaic cell, what effect would it have on the flow of ions in the Voltaic cells? Will ...
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639 views

Weird Wikipedia Section on Oxidizing Behavior of Nitric and Sulfuric Acids

It has been my understanding that when nitric, perchloric, or sulfuric acids act as oxidizing agents, they must exist as whole $\ce{HNO_3}$ or $\ce{HClO_4}$ or $\ce{H_2SO_4}$ molecules that are still ...
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Clear definition of a 'non-oxidizing acid'?

From the Beryllium article on Wikipedia: Beryllium dissolves readily in non-oxidizing acids, such as $\ce{HCl}$ and diluted $\ce{H2SO4}$, but not in nitric acid or water as this forms the oxide. ...
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Why does carbon(monoxide) reduce iron ions?

Based on the electronegativity and ionization values of carbon and iron it does not seem logical that during the production of iron from iron-oxide carbon would reduce iron ions as carbons ...
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48 views

How does a copper piece added in nitric acid change after nitrogen dioxide starts appearing?

There's an experiment I have no way of performing but want to know its results. The instructions (in short) are: Dip a piece of copper in a glass of concentrated nitric acid, $\ce{HNO3}$, using a ...
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24 views

Half cell reactions for oxidation of water by acidified solution of potassium dichromate

From Chemguide: I don't understand the first equation. The chromium atoms in the dichromate ion receive 6 electrons, and their oxidation state declines from 6+ to 3+. But where do the 14 hydrogen ...
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17 views

Mid point reduction potential

A solution of $100\ \mu \mathrm{mol\ L^{-1}}$ nicotinamide adenine dinucleotide has an absorbance of $340\ \mathrm{nm}$ of zero when in the $100\%$ oxidized form and $0.0622$ when in the $100\%$ ...
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29 views

Removing aluminum “corrosion?”

I have some aluminum alloy, possibly 6063 or 7050 (no clue really) which has corroded. The finish might be silver-anodized but I doubt it due to the high polish, could be urethane. The item is a ...
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382 views

Why does sodium produce predominantly sodium peroxide when burned in air?

From Wikipedia's article on sodium: When burned in dry air, it forms primarily sodium peroxide with some sodium oxide. We know that sodium has a strong reducing capacity, so why does it produce ...
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61 views

Which alcohols change CrO3/H2SO4 from orange to green? [closed]

Which of the following sets of compounds cannot turn a clear orange solution of $\ce{CrO3/H2SO4}$ to a greenish opaque solution? (More than one answer is correct) A) Ethanol B) ...
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48 views

Can oxidation of ethanol by copper(II) oxide yield copper(I) oxide as one of the products?

We know that ethanol is oxidised by copper(II) oxide to an aldehyde. Copper is reduced from $\ce{Cu^2+}$ to $\ce{Cu}$. Can this reaction, with some specific condition, yield $\ce{Cu2O}$ instead? That ...
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In a galvanic cell where the two electrodes are in the same electrolyte solution, why do reduction and oxidation occur separately?

In a certain book, I was presented with the following solution: An iron nail is attached by a piece of wire to a magnesium ribbon, and the iron and magnesium are placed into the same container, with ...
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172 views

Why does LiAlH4 reduce an amide to an amine but only reduce a ketone/aldehyde to an alcohol?

Here are two different reactions in which lithium aluminium hydride, $\ce{LiAlH4}$, reduces a carbonyl group: Why does $\ce{LiAlH4}$ completely remove the oxygen from the amide but only reduces the ...
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32 views

Isn't the reaction of chloral with sodium hydroxide a disproportionation reaction?

Chloral undergoes a haloform reaction with sodium hydroxide. Now the carbon atoms in chloral are in the $\mathrm{+III}$ and $\mathrm{+I}$ oxidation state. Chloroform’s carbon is in the $\mathrm{+II}$ ...
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364 views

How does aluminium react with bases to form aluminates?

An example of reaction: $$\ce{2Al + 2KOH + 6H2O->2 K[Al(OH)4] + 3H2 ^}$$ Aluminium is not ionic, how then does it attract the $\ce{OH-}$ groups to bond with them into the complex ion ...
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56 views

Reaction of chlorine with hot/cold solution of hydroxide

When chlorine reacts with cold solution of say potasium hydroxide, the disproportionation goes to lower oxidation states: $\ce{Cl2 + 2 KOH -> KCl + KClO + H2O} $ Whilst with hot solution the ...
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34 views

Which species gives electron in the following reaction?

In a given reaction like this: $$\ce{FeO4^2- + 3e^- + 8H+ <=> Fe^3+ + 4H2O}$$ From where does the electron come in the acidic medium, as there is no other species to get oxidised in the ...
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23 views

How to calculate n factor for salts in this reaction?

My source says : For salts which react such that no atom undergoes change in oxidation state , n-factor for such salt is the total moles of cationic /anionic species replaced in 1 mole of the salt . ...
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39 views

Can I convert elemental nitrogen to nitrous oxide?

Can I convert nitrogen to $\ce{N2O}$, to conduct barking dog reaction, where it's needed as oxidizer?
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25 views

Cell Potential Problem with Unusual Electrode

The problem reads: Calculate the cell potential, $E$, for a silver-silver chloride electrode immersed in $0.800~\mathrm{M}$ $\ce{KCl}$ at $298~\mathrm{K}$. Given: $$\begin{align} ...
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19 views

Chemistry Redox Reactions

$$\ce{SO4^2- + H2O2 + 2H+ -> SO2 + O2 + 2H2O}$$ In the above chemical reaction,I am having trouble in identifying the oxidized a reduced species. My guess is: sulfur has reduced but I can't work ...
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33 views

How to balance a redox equation in molecular form?

I've spent a while trying to balance this equation in molecular form with no success. $$\ce{Cu + HNO3 -> Cu(NO3)2 + 2NO + H2O}$$ I need to find the coefficient of HNO3, which is 8. However, this ...
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206 views

How to identify a redox reaction?

I don't understand how to identify a redox reaction. The answer key shows the correct answer as D, but I'm confused as to why. Which balanced equation represents a redox reaction? $$A. ...
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56 views

Stereoselectivity differences in Lindlar's catalyst and Na/NH3?

Why does using the Lindlar's catalyst form cis-alkenes whereas $\ce{Na/NH3}$ forms trans-alkenes?
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25 views

Which procedure(s) will allow a student to differentiate between solid sodium sulfate and solid sodium sulfite?

I. Make solutions of each and look for a precipitate when added to 0.10 M Ba(NO3)2. II. Add crystals of each to 0.10 M HCl and watch for bubbles. III. Make solutions of each and test with a pH ...
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How can chlorine have an oxidation number of 3 in chlorite?

I am studying redox reactions right now and I'm a bit confused about something: $\ce{ClO2^-}$ is a compound ion and in a compound ion the sum of oxidation state of participating ions has to be equal ...
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Mechanism of the oxidation of alcohols with KMnO4

Many oxidising agents, like chromate, dichromate, iodine in $\ce{NaOH}$ etc. seem to work via ester formation and elimination. For example, chromic acid will react with the $\ce{-OH}$ of alcohol to ...
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46 views

Why is sulfuric acid used in the Jones oxidation of alcohols?

When oxidising primary alcohols, $\ce{K2Cr2O7}$ is used because it's a useful & readily available oxidising agent. Why does the sulfuric acid need to be added? Does it have to do with the ...
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Is it possible to write a redox reaction with two oxidations and one reduction together?

Let's take the Redox reaction between ${MnO_4}^-, {C_2O_4}^{2-}$ and ${SO_3}^{2-} $ Is it possible to write the complete reaction as below or do I need to consider the two reactions separately? ...
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Electrode Potentials, Redox Reactions

Construct a balanced equation for the reaction between $\ce{Cr^2+}$ ions and $\ce{Cr2O7^{2-}}$ ions in acid solution and calculate the standard potential. In my answer I wrote this equation : ...
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58 views

How to balance the reaction equation of potassium permanganate, calcium oxalate, and sulfuric acid step by step?

I have been desperately trying to balance the following equation, and finally (ultima ratio) used an online program to get it done (posted the same question there as well). $$\ce{KMnO4 + CaC2O4 + ...
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70 views

What is the pH of the solution (redox question)?

For the following reaction: $$\ce{NiO2(s) + 4 H+(aq) + 2 Ag(s) -> Ni^2+(aq) + 2H2O(l) + 2Ag+(aq)}$$ $$ E^\circ = 2.48\ \mathrm V$$ Calculate the $\mathrm{pH}$ of the solution if $E = ...
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The reaction between nitric acid and iron II sulfide

...yields NO2, H2O, Fe3+, and S. I can spot the half reactions reducing the nitric acid to NO2 and H2O and oxidizing the Fe2+ to Fe3+, but how does S2- get oxidized to S? I am not familiar with this.
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41 views

Experimentally finding order of a reaction

For the reaction of bromocresol green and bleach, I was supposed to conduct an experiment to find the order of the reaction with respect to bleach. To do this, I used a fixed amount of bromocresol ...
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Which substance participates readily in both acid-base and oxidation-reduction reactions?

Which substance participates readily in both acid-base and oxidation-reduction reactions? $\ce{Na2CO3}$ $\ce{KOH}$ $\ce{KMnO4}$ $\ce{H2C2O4}$ And why? I know $\ce{KOH}$ ...
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39 views

Adding reduction potentials?

Will it be wrong to add reduction potentials of two intermediate reactions to get reduction potential of net reaction(just like as we do in adding enthalpies and applying Hess's law)? What is the ...
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Will bases typically precipitate silver atoms from silver ions?

In class I learnt that one can dissolve many substances using acid and that this can be predicted using standard electrode potentials. For example, $$\begin{align} \ce{Zn &-> Zn^{2+} + 2e^-} ...
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194 views

Fe 2+ and MnO4- titration?

As a lab experiment, I am preparing a mixture of iron tablets dissolved in sulfuric acid so they can be titrated against $\ce{MnO4-}$. The tablet contain insoluble filler material. Why is it ...