Net ionic equation and Redox equation confused

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Discussion Overview

The discussion revolves around writing the net ionic equation for the reaction between sulfuric acid (H2SO4) and potassium permanganate (KMnO4), with a focus on distinguishing between net ionic and redox equations. Participants explore the complexities of identifying oxidizing and reducing agents in this context, as well as the implications for laboratory procedures.

Discussion Character

  • Homework-related
  • Debate/contested
  • Exploratory

Main Points Raised

  • One participant expresses confusion about when to use redox versus net ionic equations, noting they obtained different answers using two methods.
  • Another participant claims there is no reducing agent present in the reaction, suggesting something is amiss with the initial setup.
  • A participant questions whether water acts as a reducing agent in the reaction.
  • One participant proposes a half-reaction for the oxidation of permanganate, suggesting that water is the sole reducing agent, while another counters that it is actually the oxygen from permanganate that is oxidized.
  • Several participants discuss the implications of adding sulfuric acid directly to the KMnO4 solution in a lab context, raising concerns about the appropriateness of this approach.
  • One participant mentions that sulfuric acid is necessary to achieve a high enough oxidation potential for the permanganate solution.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the presence of a reducing agent or the correct approach to writing the equations. Multiple competing views remain regarding the roles of water and permanganate in the reaction.

Contextual Notes

Participants express uncertainty about the definitions and roles of oxidizing and reducing agents in this specific reaction, as well as the implications for laboratory practices. There are unresolved questions about the decomposition of permanganate and its classification as a redox reaction.

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Homework Statement


Write the net ionic equation for H2SO4(aq) to the KMnO4(aq)

Homework Equations


The Attempt at a Solution


I am confused on which one should i write.
The first method is to list all the species, then use the data book to find which one is the strong OA and SRA. Multiply one or both half equation by the number that will bring the number of electrons to the lowest common multiple. Add them together and cancel the identical ion.
The second is net ionic equation, H+ +SO4- + K+ MnO4- --> ...
I got two different answer. I have to no idea when to use redox or net ionic...
If anyone can tell me the difference...
thanks
 
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There is no reducing agent in the question; something is wrong.

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Isn't water act as RA?
 
And what is it oxidized to?

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I don't know, but this is i work...
H+ SO42- K+ MnO4- H2O
SOA: MnO4- + 8H+ +5e---> Mn2+ + 4H2O
since H2O is the only RA, so water will be the SRA
SRA: 2H2O ---> O2 + 4H+ +4e
the balanced redox equation:
4MnO4- + 12H+ ---> 4Mn2+ + 6H2O + 5O2
 
Last edited:
In permanganate decomposition it is not water that is getting oxidized, but oxygen from permanganate.

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I don't understand...:\
How can i solve it?
Btw, The followed question is why it would not be a good idea for us to add the H2SO4 directly to the KMnO4 solution during this lab?
this is one of my lab question. In the lab, we were trying to find the concentration of KMnO4 using the primary standard, and then use the calculated concentration to find another concentration of the H2O2 solution.
H2SO4 was added into the primary standard and H2O2 solution..
 
Last edited:
Nope said:
I don't understand...:\
How can i solve it?

I told you much earlier - there is no reducing agent in the system. To some extent there is no solution - unless you will treat decomposition of the permanganate as redox reaction, but then both reduction and oxidation occur in the same molecule. Which technically can be classified as redox.

Btw, The followed question is why it would not be a good idea for us to add the H2SO4 directly to the KMnO4 solution during this lab?

Read about solutions used in permanganate titration.

this is one of my lab question. In the lab, we were trying to find the concentration of KMnO4 using the primary standard, and then use the calculated concentration to find another concentration of the H2O2 solution.
H2SO4 was added into the primary standard and H2O2 solution..

http://www.titrations.info/permanganate-titration

Sulfuric acid is necessary to have high enough oxidation potential of the permanganate solution.

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methods
 

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