Onsider the following unbalanced chemical equation for the reaction which is used to determine blood alcohol levels: h1+ + cr2o72- + c2h6o → cr3+ + co2 + h2o in the forward reaction, is chromium oxidized and/or reduced?

Chromium is reduced in forward reaction

Explanation:

A species is said to be oxidized if oxidation number of the species increases.

A species is said to be reduced if oxidation number of the species decreases.

Oxidation number of Cr in = +6

Oxidation number of Cr in = +3

So change in oxidation number of Cr in forward reaction = (+3)-(+6) = -3

Hence oxidation number of Cr decreases on going from   to  .

So, chromium is reduced in forward reaction.