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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CO detector reaction [on hold]

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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Principles Used to Predict if a Reaction Will Occur? [on hold]

Just left high school, and I want to know how I should be able to tell whether an element will react with another one. I also want to know how i should be able to tell whether a molecule will react ...
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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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91 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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33 views

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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1answer
39 views

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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3answers
49 views

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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1answer
44 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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41 views

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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1answer
85 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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1answer
108 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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1answer
260 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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2answers
23 views

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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1answer
39 views

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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33 views

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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1answer
39 views

How does Zinc become oxidized when it's not in direct contact with Copper ions in a Galvanic cell?

Whenever 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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1answer
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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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2answers
48 views

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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2answers
88 views

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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3answers
54 views

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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32 views

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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1answer
66 views

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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38 views

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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141 views

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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2answers
134 views

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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1answer
103 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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1answer
40 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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1answer
48 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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34 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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26 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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35 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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48 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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What is the chemistry behind cleaning silverware with aluminium foil

This question has a accepted answer on this site already: What happens during cleaning silverware? but the reason I ask the question again is because I found different "recipes" for the technique ...
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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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78 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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76 views

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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47 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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34 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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1answer
75 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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1answer
36 views

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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57 views

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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37 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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1answer
70 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: $\ce{5NO2- + 2MnO4- + 6H+ -> 5NO3- + 2Mn^{+2} + 3H2O}$ ...