Consider the reactions
(A) H2O2 + 2HI → I2 + 2H2O
(B) HOCl + H2O2→ H3 O+ + Cl- + O2
Which of the following statements is correct about H2O2 with reference to these reactions? Hydrogen perioxide is _______
An oxidising agent is one which oxidises(oxidation number increases) others and itself gets reduced. Whereas a reducing agent reduces (oxidation number decreases) others and itself gets oxidised.
So, we can see that H2O2 acts as an oxidising agent in (A) as it increases the oxidation number of I- in HI from -1 to 0 in I2.
Similarly, H2O2 acts as a reducing agent in (B) as it decreases the oxidation number of Cl+ in HOCl from +1 to -1 in Cl-.