-1
$\begingroup$

Does it count as an autoredox reaction if two different elements from the same polyatomic ion or molecule change their oxidation numbers? For example, for a reaction like this:

$$\ce{2KNO3(s) -> 2KNO2(s) + O2(g)}$$

Here, the nitrogen and oxygen in the nitrate ion undergo oxidation and reduction to from nitrite and diatomic oxygen, respectively. Does this count as a redox reaction since the same polyatomic ion undergoes both?

In my text book, it says that when an element in a molecule or polyatomic ion undergoes reduction or oxidation, we refer to the entire molecule or ion as being reduced or oxidized. I don’t know what effect this has on this reaction though.

$\endgroup$
  • $\begingroup$ Yes, this is a particular type of redox reactions known as disproportionation reactions. $\endgroup$ – ralk912 Mar 25 '18 at 6:55
  • $\begingroup$ Hi dahen! Please use mathjax to format questions and answers! Thanks. $\endgroup$ – MollyCooL Mar 25 '18 at 7:27
  • $\begingroup$ @MollyCooL sorry about that, I'm on phone right now so it was kind of inconvenient to do it $\endgroup$ – Dahen Mar 25 '18 at 7:42
0
$\begingroup$

Any reaction in which one atom/ion loses some electrons and any other atom/ion gains those electrons is a redox reaction.

In your particular example, the oxygen atom is losing its electrons and the nitrogen atoms are gaining those electrons. So, it is definitely a redox reaction.

The reaction in which atoms from the same species are oxidised and reduced are called disproportionation reaction. So, the same reaction is also a disproportionation reaction.

Look at these examples too, disproportionation reaction

In both of these examples, the same molecule/ion/atom undergoes an oxidation as well as a reduction, so these are also disproportionation reaction.

Note that every disproportionation reaction is a redox reaction.

$\endgroup$
  • 1
    $\begingroup$ You should cite figures that you didn't personally make. $\endgroup$ – ralk912 Mar 25 '18 at 7:29

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.