Redox (reduction–oxidation, pronunciation: RED-oks or REE-doks) is a type of chemical reaction in which the oxidation states of atoms are changed. Redox reactions are characterized by the actual or formal transfer of electrons between chemical species, most often with one species (the reducing agent) undergoing oxidation (losing electrons) while another species (the oxidizing agent) undergoes reduction (gains electrons). The chemical species from which the electron is removed is said to have been oxidized, while the chemical species to which the electron is added is said to have been reduced. In other words:
Oxidation is the loss of electrons or an increase in the oxidation state of an atom, an ion, or of certain atoms in a molecule.
Reduction is the gain of electrons or a decrease in the oxidation state of an atom, an ion, or of certain atoms in a molecule (a reduction in oxidation state).Many reactions in organic chemistry are redox reactions due to changes in oxidation states but without distinct electron transfer. For example, during the combustion of wood with molecular oxygen, the oxidation state of carbon atoms in the wood increases and that of oxygen atoms decreases as carbon dioxide and water are formed. The oxygen atoms undergo reduction, formally gaining electrons, while the carbon atoms undergo oxidation, losing electrons. Thus oxygen is the oxidizing agent and carbon is the reducing agent in this reaction.Although oxidation reactions are commonly associated with the formation of oxides from oxygen molecules, oxygen is not necessarily included in such reactions, as other chemical species can serve the same function.Redox reactions can occur relatively slowly, as in the formation of rust, or much more rapidly, as in the case of burning fuel. There are simple redox processes, such as the oxidation of carbon to yield carbon dioxide (CO2) or the reduction of carbon by hydrogen to yield methane (CH4), and more complex processes such as the oxidation of glucose (C6H12O6) in the human body. Analysis of bond energies and ionization energies in water allow calculation of the redox potentials.
Homework Statement
Hydroxylammonium chloride reacts with Iron(III)chloride (FeCl3) in solution to produce Iron(II)Chloride, HCL, H2O, and a compound of nitrogen. It was found that 2.0 g of iron(III) chloride reacted in this way with 31 mL of 0.200 M hydroxylammonium chloride.
Suggest a...
Homework Statement
Balance the equation for disproportionation reactions.
Homework Equations
S8(s) ----> S2-+S2O32- (basic solution)
The Attempt at a Solution
I attempted into do this with the ion electron method, obtaining an answer:
3S8 + 24OH- ----> 16S2- + 4S2O32- +...
hey I'm in yr 12 chemistry in Australia and I am having problems understanding redox reactions equations, i understand oxidation states and a little bit but i can't figure our about the electrons calculus, i can do the rest of the formula or steps but i cannot seem to be able to calculate the...
Hello guys. I have been a lurker at these forums for quite a while now, they are very helpful if you have run into a snag in your homework. :)
What I have here is a redox reaction, and I will be very grateful if someone could confirm my answers.
H+...
Homework Statement
Give the net redox equations for the following reactions which occur in base solution.
Fe(OH)_2+ O_2 \rightarrow Fe(OH)_3
Homework Equations
noneThe Attempt at a Solution
The oxidation half reaction is Fe(OH)_+OH^{-1}\rightarrow Fe(OH)_3 + e^{-}.
How do we find the...
Redox reactions can take place in both acid or basic solutions, that I know. But, what if the type of solution in which the reaction occurs is not given? Am I to assume it is acid or basic?
1. What volume of a 0.0200 M KMnO4 solution is required to oxidize 40.0 mL of 0.100 M FeSO4 in sulfuric acid solution?
2. MnO4-1 + H+ + Fe+2 --> Fe+3 + Mn+2 + H2O
3. I honestly have no idea how to tackle this, I failed the titration portion of the AP Exam. I Think is maybe...
Homework Statement
I have to calculate the redox potential of this equation:
Cr2(SO4)3 + 4K2SO4 + 3J2 +7H2O <=> K2Cr2O7 + 6KJ +7H2SO4
I used the nernst equation to calculate the potentials of
2Cr(3+)+7H2O -> Cr2O7(2-) +14H(+) +6e(-) and
I2 +2e(-) ->2J(-)
which were -1.42V and 0.51V, all...
[SOLVED] Redox titration help
Hi
In class we are doing a redox titration with a diluted bleach solution. We made the aliquot with 5 ml of 10% KI solution and 5ml H2SO4 with 25 ml of the diluted bleach solution. And the burrette solution was sodium thiosulfate @ 0.1 mol L-1. my results were as...
determine the % of iron II and iron III in a mixture containing both, where i am given 200cm3 of a solution containing 1.3g of iron ions(Fe 2+ Fe 3+) using potassium magnanete.
I wrote down the equation already, and method, but i don't know how to work out the % from it :/
Can you please help...
Help me please to finish this reaction of the ferrocyanide reduction:
K3Fe(CN)6 + Na2S2O3 + H2O=...?
the electron transfer reaction inthis case is
2Fe(CN)3-6 + 2S2O3 = 2Fe(CN)4-6 + S4O2-6.
Wondering what are the final products of the upper reaction.
I'm trying to find out what type of reaction this is.
a drop of water is added to a small pile of chemicals in a dish, after a few seconds, a blue flame and smoke is produced.
NH4NO3 reacts to form (with chlorine as catalyst) N2O and water
the experiment is called oxidation of zinc, so...
I am performing a REDOX titration of a diluted bleach sample in my analytical chemistry class. I am using sodium thiosulfate as the titrant to determine the amount of sodium hypochlorite ion in solution. I am using a starch indicator, which is supposed to turn from blue to colorless at the...
Homework Statement
For those who have mastered the balancing of any type o redox equation, an extra challenge is provided below. Balance each of the following equations. Note: all of the reactions take place in aqueous solution.
Homework Equations
HIO3 + FeI2 + HCl ====> FeCl3 + ICl +...
1. Oxalic acid, H2C2O4, reacts with dichromate ion, in acidic solution to produce carbon dioxide and chromium(III) ion.
If exactly 50.0 mL of an oxalic acid solution is required to react completely with 25.0 mL of a 0.0100 M dichromate solution, what is the molarity of the oxalic acid...
Homework Statement
Balance this redox equation.
Homework Equations
Ag + H^{+} + NO_{3} ^{-} \rightarrow Ag^{+} + H_{2}O + NO
The Attempt at a Solution
Using a conventional balancing mechanism I got these coefficients:
1 + 8 + 2 -> 1 + 4 + 2
but the correct...
Homework Statement
“From knowledge of oxidation states of nitrogen in the product as determined experimentally, and the oxidation state of nitrogen in each species in the list of possible products, select the most likely product of the following:
….NO3- (I found this to be the product)...
Balancing a Redox Reaction.. urgent
I have an assingment that is due tomorrow for my college chemistry class and i am stuck on the last problem. I need to balance the following redox reaction, but everytime i try it doesn't balance...
H2O +I2 + OCl- ? IO3- + Cl- + H3O
when i split it up...
im currently studying redox in chemistry and I am really enjoying it so far.
I am just a little bit confused about one section of it, that is that i cannot understand how to work out the product in the 1/2 equations ..
e.g Fe2+ forms Fe3+.. but why does it form this.. i know iron is a...
Homework Statement
Write the half equation for the cathodic reaction of oxygen
The Attempt at a Solution
Now I know that the cathodic reaction will be reduction and so the oxygen will be gaining electrons. I thought I had the answer from the lecture notes, but then I thought of another...
Homework Statement
Identify the oxidizing agent and the reducing agent and write a balanced equation for each half reaction.
MnO4(1-) + VO(2+) ----> Mn(2+) + V(OH)4 (1+)
Homework Equations
None.
The Attempt at a Solution
I know how to do these when there is just one atom...
Nowhere in my notes does it say what Eθ is and i can't find a definition of it on the internet :confused:
I'll give you the context:
For group 2 of the periodic table, state and explain the trends in the following for their elements:
(i) redox property, related to Eθ value
Homework Statement
Cl2 -> Cl- + ClO3-
(in basic solution)
Homework Equations
The Attempt at a Solution
Well, I've tried messing around with the half reactions but since Cl2 is involved in both, they don't seem to do much good.
e + Cl2 -> Cl-
Cl2 -> ClO3- + 5e
Normally, I would multiply the...
Homework Statement
A sample of iron ore consisting of a mixture of FeO and Fe2O3 was dissolved in dilute sulfuric acid. The resultant solution was divided into two equal aliquots. The first aliquot was titrated with a potassium permanganate solution containing 6.30g of KMnO4 per litre, and...
Homework Statement
Balance the following redox equation (in an acidic solution):
Cu + NO3- -> NO2 + Cu2
The Attempt at a Solution
I got 4H+ + 2NO3- + Cu -> Cu+2+ + 2NO2 + 2H2O
But my book told me the same thing, but without the H2[/sub]O:
4H+ + 2NO3- + Cu ->...
Homework Statement
1) Give the resultant fomula for: Cr2+ gets reduced.
2) Will the following reaction occur? Acidified K2Cr2O7 solution is added to HNO3(nitric acid).
Homework Equations
N/A
The Attempt at a Solution
1) I put: Cr+2 + 2e- ---> Cr(s); I have one question...
I'm working on a chemistry assignment that involves creating redox tables. The explanation in the textbook isn't a very good one and I can't find my answer through google either :mad:
Here's the problem:
The following equations represent spontaneous reactions. From this evidence, set up a...
Homework Statement
Excess acidified potassium permanganate is added dropwise to an ammonium iron(II) sulfate solution. Write an overall redox equation for this process.
2. The attempt at a solution
Well I am not really sure what to do. I don't know what products are being formed. What...
Homework Statement
I basically have 4 sets of solutions which I have to write the chemical reactions for. I already figured out the chemical formulas for the reactants, and just need help determining the final products. I know how to balance, and just need help determining the products...
What is the point of using the redox convention in describing reactions involving covalently bonded species? To me it is a very unnatural thing to do? A reaction can occur with a rearrangement of atoms but no change in oxidation numbers of the atoms so a redox reaction hasn't occurred but a...
Hello,
Today, we saw an experiment where an unknown yellow solution became dark blue while it was being shaken.
I have an explanation for it, but would like your opinion as well:
We had a redox reaction, with the oxidation of glucose (being the reducing agent) by NaOH (being the...
i have to balance a redox reaction that contains the cyanide ion and other stuff. but before i can do anything, i have to assign oxidation states. would hte CN- have oxidation states of C being +4 and N being -5? so then would CNO- have C be +4, N be -2, and O be -2?
I have many problesm with this question. Can somone help me please?
In a titration of patasium permanganate soloution with acidified sodium nitrate solution
MnO4- + BO2- H+ -----> Mn+2 + NO3- +H2O
45 ml of 0.05M of KMnO4 reacts complitely with 20.0 mL of NaNO2 solution.
Calculate the...
The attachment shows reactions involved in a titration experiment. In the first equation, iodate reacts with iodide in acidic solution to produce iodine. In the second equation, the iodine is titrated with thiosulfate.
I know the volume and molar concentration of iodate as well as the volume...
Hey there, recently we just did a lab in Chemistry 101 on "Redox Titrations." I'm now working on the lab writeup but was hoping that someone may be able to help me with this question I am currently stuck on. It asks the following:
A sample of Au2(C2O4)3 is contaminated with Li2(C2O4). An...
Hello,
I've been working on some redox reactions for the oxidation of manganese.
Question:
Write the complete formulae for the redox reactions below:
i.) Manganese reacts with nitric acid (V) to form Mn2+ ions.
ii.) The Mn2+ ions reacts with potassium iodate, KIO4 to form MnO4-...
hey guys! i am lost with my current unit...redox reactions. i was wondering if any chem whizzes could lead me in the right direction as how to write the oxidation and reduction equations for the following reaction:
IO-3 (aq) + I- (aq)--> I2 (aq)
Any help would be greatly appreciated! I...
I am doing Redox Equations in Acid/Base. Anyway, I have one question. I know that you multiply to get a common factor for electrons. However, after you cancel out your electrons, can you multiply by another common factor to remove water or hydrogen? I am leaning towards no, but I am not sure...
Hello. I have a question on balancing redox equations. I’ve tried to follow the steps in my book but I don’t understand how to do it. Can someone please walk me through one.
H2S(g) + NO3{-1}(aq) > NO(g) + S(s) (acidic solution)
Now the book says I have to add electrons but how?
Thanks
I am trying to write a redox reaction for Lead (II) Acetate electrolytically becoming Lead Dioxde and Lead at the anode and cathod of an electrotic cell.
I am using the redox reaction of Lead Sulfate in a car battery as a model, but mine doesn't look right.
I am not sure if I need to include...
I have been staring at the following problem, and I can't seem to get the correct answer. I tried using half reactions and the oxidation number method, but I don't know which works best.
Write balance net ionic equations for reaction in acidic solution.
ClO3- (aq) + As2S3 (s) --> Cl- (aq)...
Formation of Hydrazine from Ammonia and Chloramine in basic solution.
NH3 + NH2Cl -> N2H4 + Cl-
What are the coefficients of NH3, OH-, and N2H4 in the balanced equation?
I basically just balanced the hydrogens with an H+, then those with OH-, and got:
NH3 + NH2Cl + OH- ->N2H4 + Cl- + H2O...
I had some trouble balancing these using the "ion electron method", ordinarily I'd balance the half reactions (excluding H and O), add H20 to compensate for O, H+ to compensate for H, and electrons to compensate for charge.
P4(s) + NO3-(aq) ---> H2PO4-(aq) + NO(g) (in an acidic solution)...
Anyways, can anyone help me with this question..
In 1763, the British Admirality covered wooden ship HMS Alarm with copper sheeting to protect it from marine worms. This was sucessful but, they reported: '... we were surprised to perceive the effect of the copper had upon iron where the two...
hi all, my chemistry assignment had a bunch of questions on redox equations balancing. i got stuck on this one:
[tex] \CrI_{3} + KOH + \Cl_{2} \rightarrow \K_{2}CrO_{4} + \KIO_{4} + KCl + \H_{2}O [\tex]
so far, i tried to find ON numbers of the various elements.
Cr changes from +3 to +6...
Hi all,
The other day in chemistry class, we carried out several different redox reactions. In one set of the experiments, we reacted potassium permanganate with 3 different potassium halides (KCl, KBr, KI). this particular redox reaction also requires an acidic environment, so sulfuric acid...
Just need some idea of where to start on this one...am in my first Chemistry class and it is an intensive so we're not spending a lot of time on things. This one just has me stumped from the beginning so just some guidance on where to begin would be a huge help...
Problem: Gold metal will...
Hi,
I did a question once and in that Mno4- -> Mno2 but in another question it was Mno4- -> Mn2+
How can these equations defer and is there a way to know what the right side of the half equation is going to be when the left is given?