Consider the following reaction. What is being oxidized?

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1 Answer
Sep 12, 2017

Answer:

Dihydrogen is being oxidized.....

Explanation:

Oxidation entails a formal LOSS of electrons, and an increase in oxidation number corresponding to the NUMBER of electrons lost...

We gots zerovalent dihydrogen gas, #stackrel(0)H_2#, that is oxidized to water, i.e. #stackrel(+I)H#:

#1/2H_2(g)rarrH^+ + 1e^-# #(i)#

And since for every oxidation, every electron loss, there is a corresponding reduction, an electron gain....

#stackrel(+IV)CO_2(g)+2H^+ +2e^(-)rarrstackrel(+II)CO(g) +H_2O# #(ii)#

And so we adds, #2xx(i)+(ii)#.......to retire the electrons.....

#CO_2(g)+cancel(2H^+) +H_2(g) rarrCO(g) +H_2O+cancel(2H^+)#

To give....

#CO_2(g)+H_2(g) rarrCO(g) +H_2O#

And thus dihydrogen is oxidized and carbon dioxide is reduced......