[TrueBlood]

I can find the oxidation number of various atoms, within a molecule, without a problem.

The problem I have is understanding how certain reactions are "oxidizing" when no individual atom is being identified. For instance, many reactions where CO2 is released are oxidizing, even when no O2 was consume. Take the oxidation of pyruvate; NADH is created from NAD+ and CO2 released. What exactly are people looking at when they say the reaction is oxidizing? Are they looking at functional groups or am I missing something large here. Because I've been assuming for any oxidation to occur, some part of the reaction will be reducing. Thus, I don't get how an entire reaction can be oxidizing.


Please use the pyruvate example, as that is something I will like to know.


Thank you.

[Schrödinger]

Oxidation does not necessarily mean that O2 is being consumed. As you might already know, change in oxidation number is what decides this. It so happens that in almost all reactions that consume O2, the substrate gets oxidized.

Indeed, no oxidation can occur without there being a reduction happening elsewhere. So, when people say that the reaction is oxidizing, I assume that they are talking about a substrate that they 'want' oxidized by some reagent.