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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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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38 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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35 views

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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27 views

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 ...
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Reducing NOx with Ammonia. Practical in a gasifier?

Sorry if this is an outright stupid question. I am no chemist... For Nitric Oxide: $2{NH_{3}} + 2 NO => 2 {N_{2}} + {H_{2}} + 2{H_{2}O}$ For Nitrogen Dioxide: $2{NH_{3}} + 2{NO_{2}} => ...
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How to know if something will be a good oxidizing/ reducing agent? (Besides the activity of the metal)

One of first redox reaction I was taught in school, is probably single replacement. It is easy to predict cause all you need is a table of metal activity series. But then there are more complicated ...
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What reactions can take place for the reactants $\ce{Ag/Ca^2+}$ and $\ce{Mg/Cu^2+}$?

Explain the following experiments and their results. What is their chemical equations as well? When immersing a Magnesium (Mg) chunk inside aqueous solution of Copper ions (Cu(ii)), a red-brown ...
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32 views

Will happen or not?

I have a few questions, I'm really confused with my own answers so an explanations on why each of them can or cannot happen will be appreciated. A. Is $\ce{H+}$ capable of oxidizing $\ce{Cu_(s)}$? ...
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24 views

Oxidation of methane

In the reaction $\ce{CH_4 + 2O_2->CO_2 + 2H_2O}$ the $\ce{C}$ atom is oxidized. I can clearly see the addition of $\ce{O}$ atoms, however I don't see a change in Oxidation state. In the products, ...
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32 views

What can HI + red phosphorus reduce?

What can $\ce{HI}$ plus red phosphorus reduce? what happens if lactic acid is reduced by it? Does it reduce only the $\ce{OH}$ part, or does it reduce both the $\ce{CO2H}$ and the $\ce{OH}$ part?
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37 views

Clean silver with aluminum foil and *

I already have two questions touching on this subject and there is a third question as well. The thing is that all the other question talk about cleaning silver with aluminum foil and carbonated ...
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30 views

What is the chemistry behind cleaning silverware with aluminium foil

This question has a accepted answer on this sit already What happens during cleaning silverware? but the reason I ask the question again is because I found different "recipes" for the technique and ...
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24 views

Clean tin with aluminium

I've been using aluminium foil and table salt to clean my silverware for a long time without actually concerning myself with the chemistry behind it. A couple of days ago i started digging into the ...
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40 views

How does the oxidation of NaI by sodium hypochlorite to give I+ work?

I'm in trouble with the oxidation of NaI by $\ce{NaClO}$, the reaction should give $\ce{I+}$ which then reacts by electrophilic substitution with an aromatic complex. As of now I've come to: $$\ce{ ...
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Does Iron (III) Sulfate react with copper?

As my understanding, there should be an oxidation-reduction reaction: $$ \ce{2Fe^{3+} + Cu \rightarrow 2Fe^{2+} + Cu^{2+}} $$ However, I always see the process using $\ce{FeCl_3}$ to etch ...
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37 views

Electrophilic aromatic substitution with fluorine

Why don't we usually use diatomic fluorine in electrophilic aromatic substitution? Is it because fluorine is a potent oxidizer and will react with the carbons? What might happen if we reacted ...
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25 views

Half reaction method justification

I have to say I have never really understood the half reaction method. What bothers me is that it seems to be too artificial. Too many little rules to remember! Why don't we use the mass conservation ...
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53 views

Old samples of magnesium oxide become contaminated with magnesium carbonate. Suggest how this contamination takes place

Old samples of magnesium oxide become contaminated with magnesium carbonate. Suggest how this contamination takes place. I don't understand what I'm meant to put for this.
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Reducing agent in preparation of CpRuCl(PPh3)2

Synthesis of cyclopentadienyl-bis-triphenylphosphine-ruthenium chloride $\ce{RuCl(PPh3)2(\eta^5-C5H5)})$: Dissolved $\ce{PPh3}$, $\ce{RuCl3.3H2O}$ and cyclopentadiene in ethanol and heated under ...
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Disproportionation Reactions of the Halogens: Writing balanced net ionic equations for four reactions. See details

I first conducted the following reactions, each in separate test tubes: $\ce{NaBr}$ + $\ce{H2SO4}$ + $\ce{NaBrO3}$ $\ce{KI}$ + $\ce{H2SO4}$ + $\ce{KIO3}$ ...with water and dichloroethane added ...
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Why do Electrons leave the Zinc in a Galvanic Cell

What induces electrons to leave the atoms around the part of the zinc metal in a solution to travel up along that zinc metal and above the solution, through the wire and to the copper metal and ...
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Half Cell Method of Voltage Calculation in an Electrochemical Cell

A cell consists of a copper electrode $\ce{Cu}$, in contact with $1.800\cdot10^{-2}~\mathrm{M}$ cupric ion and a platinum electrode, $\ce{Pt}$, in contact with $1.400\cdot10^{-1}~\mathrm{M}$ ...
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36 views

Is a metal hydroxide fully or partly oxidised in insufficient base?

Firstly, my question only applies to transition metal compounds with more than one hydroxide group, otherwise it would be more obvious. The reason I'm asking is in an effort to oxidise some nickel ...
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How to efficiently reduce of ilmenite to pure titanium?

I am looking for a process in which reduces ilmenite to pure titanium with the highest yield possible. We are to use a process of our choice or one that we have created in conjunction with FactSage to ...
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46 views

What is the balanced ionic redox reaction of nitrite ions with manganate(VII) ions in acidic solution?

What is the balanced ionic redox reaction of nitrite ions with manganate(VII) ions in an acidic solution? My suggestion is: $\ce{5NO2- + 2MnO4- + 6H+ -> 5NO3- + 2Mn^{+2} + 3H2O}$ ...
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59 views

How to find the balanced reaction equation for the decomposition of potassium dichromate in non aqueous conditions?

I can't find a method to balance a reaction: the heating of potassium dichromate, which forms potassium dichromate (III), dichromate oxide (III) and oxygen. I can't add water products as $\ce{H+}$, ...
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245 views

Potassium permanganate (VII) + Glucose + Sodium hydroxide =?

I saw this experiment many times but still can'y explain why. The experiment is first prepare two solution. The first one is to dissolve potassium permanganate crystal into distilled water to form ...
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52 views

What happens when oxidizing Ni(OH)2 with a strong base?

In an aqueous solution, Nickel oxyhydroxide is oxidised with a 1:1 ratio of aqueous Sodium hydroxide. My goal is to produce Nickel oxyhydroxide ($\ce{NiOOH}$). Strong Base: $\ce{NaOH + H2O ...
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Redox Question: Concentration of Pb2+ is unknown

What is the concentration of $\ce{Pb^{2+}}$ in a lake that has a pH of 6.0 and is in equilibrium with $\ce{PbO2(s)}$ and atmospheric oxygen? $\ce{PbO2(s) +4H+ +2e- -> Pb2+ +2H2O}$ log K = 49.2 ...
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55 views

How can I balance the redox reaction of sulfur dioxide with oxygen?

How do I balance this reaction using half-redox equations? $$\ce{2SO2 + O2->2SO3}$$ My work is: Oxidation: $\ce{SO2 + H2O -> SO3 + 2e- + 2H+}$ Reduction: $\ce{H2O + 2e- + O2 -> SO3 + ...
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Does it matter if all rust is removed before it is painted over?

In the context of automobile repair work, assume a metal surface has rust over it. Does it matter if all of the rust is removed before the metal surface is painted? If it does matter, then why? It ...
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54 views

Reactions that occur at the anode electrode of electrolysis dilute H2SO4

How to know that reaction that occur at the anode electrode is $\ce{2H2O -> 4H+ + O2}$? Why the reaction is not the oxidation of $\ce{SO4^{2-}}$? This problem does not give the E0 of ...
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What does oxidizing strength mean?

What does oxidizing strength mean? Does it mean the strength of a oxidation agent that is needed to oxidize the reduction agent, or does it just mean the tendency of a substance to lose electrons ...
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which substance has the higher oxidation strength?

I have to decide which one has a higher oxidation strength $\ce{ClO-}$ or $\ce{Cl2}$ $\ce{ClO- + H2O + 2e- -> Cl- + 2OH-}$ $\ce{Cl2 + 2e- -> 2Cl-}$ Will this reaction occur? $\ce{ClO- + H2O ...
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73 views

How does a redox reaction between NaClO and KBr take place? will bromide be oxidised to bromine?

How does a redox reaction between $\ce{NaClO}$ and $\ce{KBr}$ take place? will bromide be oxidised to bromine? $\ce{2Br^{−} + ClO^{−} + H2O ⟶ Cl^{−} + 2 OH^{−} + Br2}$ or will bromide be oxidised ...
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42 views

How does a redox reaction between ClO- and Br- take place?

How does a redox reaction between $\ce{NaClO}$ and $\ce{KBr}$ take place? will bromide be oxidised to bromine? $\ce{2 Br- + CIO- + H2O -> Cl- + 2 OH- + Br2}$ or will bromide be oxidised to ...
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Does bleach turn a substance white or colorless?

From what I understand, bleach works to weaken the ability of a substance to absorb light. Thus this seems to be "whitening" i.e. reflecting all light. In contrast, colorlessness (according to ...
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Why would electrode reaction in galvanic cell stop when there's no neutrality in each cell?

I know that the salt bridge produces ions to balance out the positive and negative ions in each solution, but why won't it work without a salt bride? Would it even work at the start since there's few ...
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1answer
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Terminology of redox reactions: which species are the oxidizing and reducing agents?

I've got a question regarding 'notation' for redox reactions. Suppose you are asked to identify the oxidizing and reducing agents for a simple reaction like this one: $$\ce{Cl2(aq)}+\ce{2KI(aq)} ...
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588 views

Is there non-redox reaction?

Redox reaction is a type of chemical reactions, and the result of electron transfer. But all chemical reactions are somehow involved electron transfer! Are there chemical reactions without electron ...
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56 views

Use The Half Reaction Method to Balance the Following Equation in Acidic Solution [closed]

$\ce{Fe^2+ + MnO4- -> Fe^3+ + Mn^2+}$ What steps should I take?
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Nernst equation and electrolysis

Let's say we have a stable solution of $\mathrm{A}_{\left(\mathrm{aq}\right)}^{2+}$ and $\mathrm{C}_{\left(\mathrm{aq}\right)}^{+}$ , with their respective counter-ions. The associated redox ...
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How does copper reduce dilute nitric acid to nitric oxide and concentrated nitric acid to nitrogen dioxide?

Here are the 2 equations: $\ce{3Cu + 2NO3- + 8H+ <=> 3Cu^2+ + 2NO + 4H2O}$ ${E = 0.62V}$ $\ce{3Cu + 2NO3- + 4H+ <=> 3Cu^2+ + 2NO2 + 2H2O}$ ${E = 0.45V}$ The Nernst equation tells us ...
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What exactly is net ionic equation?

I once saw a problem, iron ions(II) titrated with potassium dichromate to produce Fe(II) and Cr(III). If I am to write the net ionic equation of this reaction, I got to make potassium dichromate on ...
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51 views

In this simple redox reaction, why does the Hydrogen oxidize the calcium metal?

I am understanding that the Hydrogen ions oxidize the calcium metal, neutralizing itself and creating a calcium cation. My question is why does the Hydrogen oxidize the calcium? Doesn't it prefer to ...
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104 views

Redox reactions - alkene to alcohol

How is the "correct" answer not a redox reaction? Isn't the "correct" choice a textbook example of an organic redox reaction? After all, we are breaking a C-C bond and replacing that with a C-O ...
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57 views

Standard electrode potential for electrolytic vs galvanic cells

Whys is the standard electrode potential (-) for electrolytic cells but positive for (+) galvanic cells. If E°cell > 0, then the process is spontaneous (galvanic cell) If E°cell < 0, then ...
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How does salt and water promote corrosion?

I was always wondering why iron only rusts when it gets wet. I know that for example aluminium oxidises on its own on regular basis. I also heard many complains that salt used to remove snow from ...
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Balancing the redox reaction

Question: Balance the following redox reaction: $$\ce{FeS2 + O2 -> Fe2O3 + SO2}$$ My Efforts: I tried balancing with oxidation number method. First of all i determined the oxidation ...