Sciencemadness Discussion Board

Help with reducer, oxidizer, redox reaction..

Ashendale - 4-4-2006 at 09:41

I need help. I have a problem with identifying oxidizer or reducer quickly. Sure I can do it like so: "Hmm, okay, so umm, copper went from +1 to +2...so it gave one electron, okay, reducer is a thing that gives electron, so copper reduced..."

But that takes me hell of a time. I took the old book, but I still can't get it clear. Is there a way to remember, which is reducer, which is oxidizer and which reduces and which oxidizes?

I just keep mixing them up and I would really like to get it right..

Thanks in advance.

Odyssèus - 4-4-2006 at 10:16

Oxidising agents get reduced and recieves/accepts electrons. Reducing agents get oxidised and donates/loses electrons.

The way I remember it is that an oxidising agent for example, doesnt oxidise itself but something else, so it gets reduced. As for which one gains and which one loses electrons... reducing agents reduce the number of electrons the agent has. ;)

Darkblade48 - 4-4-2006 at 12:35

Quote:
Originally posted by Ashendale

But that takes me hell of a time. I took the old book, but I still can't get it clear. Is there a way to remember, which is reducer, which is oxidizer and which reduces and which oxidizes?

I don't suppose memorizing a table of reduction potentials is what you had in mind? I think this is the only way to do it (or with enough practice, you'll have a feel for what will reduce what)

Ashendale - 5-4-2006 at 08:28

Quote:
Originally posted by Darkblade48
I don't suppose memorizing a table of reduction potentials is what you had in mind?


Of course not, though it would be a great challenge :P

At the moment I'm writing reactions and trying to identify oxidizer / reducer as quicky as possible, though I'm still mixing them up..Guess, as Darkblade48 said, the skill will come in time.
If anyone had a problem with this too, could you please share how did *you* learn it?

Magpie - 5-4-2006 at 09:39

I think practice is the best way. There are a limited number of "usual suspects", i.e., Mn, Cr, Fe, etc and you get used to what happens to them in redox equations.

I always had to determine what was happening to the valence, as you have shown. Also remember that whether an element is reduced or oxidized depends on the situation. E.g., NO2- can be either an oxidant or a reductant, depending on what it is "competing" against.