• # question_answer 9) The reaction in which hydrogen peroxide acts as a reducing agent is A)  $PbS+4{{H}_{2}}{{O}_{2}}\to PbS{{O}_{4}}+4{{H}_{2}}O$B)  $2KI+{{H}_{2}}{{O}_{2}}\to 2KOH+{{I}_{2}}$C)  $2FeS{{O}_{4}}+{{H}_{2}}S{{O}_{4}}+{{H}_{2}}{{O}_{2}}\to F{{e}_{2}}{{(S{{O}_{4}})}_{3}}+2{{H}_{2}}O$D)  $A{{g}_{2}}O+{{H}_{2}}{{O}_{2}}\to 2Ag+{{H}_{2}}O+{{O}_{2}}$

In $A{{g}_{2}}O$ (O.N. of $Ag+1$) in $Ag$ the O.N. is O. There is gain of electrons, hence ${{H}_{2}}{{O}_{2}}$ is lasting as reducing agent.