In the reaction #2H_2S+SO_2 -> 3S+2H_2O#, what has been oxidized and what is the oxidizing agent?

1 Answer
Feb 10, 2017

Answer:

Sulfide has been oxidized, and sulfur dioxide is the oxidizing agent.

Explanation:

This is an example of a comproportionation reaction in which sulfur compounds, in different oxidation states with respect to the sulfur, undergoes electron transfer to give a elemental sulfur (which is zerovalent).

#2H_2S rarr S +2H^(+) + 2e^-# #(i)#

(oxidation from #S(-II)# to #S(0)#)

#SO_2 + 4H^(+) + 4e^(-) rarr S + 2H_2O# #(ii)#

(reduction from #S(+IV)# to #S(0)#)

So #2xx(i) +(ii)# #=# #2H_2S +SO_2 rarr 3S +2H_2O#