How do you determine the oxidizing agent in a reaction?

1 Answer
Dec 23, 2016

Answer:

The oxidizing agent is the species that accepts electrons.........

Explanation:

.........and thus is the species that is reduced in a redox reaction.

If we look at, say, the combustion of coal:

#C(g) +O_2(g) rarr CO_2(g)#

Zerovalent oxygen gas oxidizes zerovalent carbon to give #""^(+IV)CO_2^(-II)#, in which the oxygen has been formally reduced, and the carbon formally oxidized.

And of course we can artificially split these reactions up to give separate oxidation/reduction reactions, for instance,

#Na rarr Na^(+) + e^(-)#

#1/2Cl_2 +e^(-) rarr Cl^-#

And overall, we simply sum the reactions directly:

#Na +1/2Cl_2 rarr Na^(+)Cl^-#

And thus, again, the oxidizing agent is the brute that accepts electrons, which here is clearly?