Discussion Forum

For the reaction, 

$I^{-}+CiO_3^-+H_{2}SO_{4}\rightarrow Cl^{-}+HSO_{4}^{-}+I_{2}$  the correct statement(s)  in the balanced equation is/are

Answer:

Explanation:

 Plan. This problem includes the concept of redox reaction. A redox reaction consists of oxidation half-cell reaction and reduction half-cell reaction.

 Write both half-cell reactions, i.e, oxidation half-cell reaction and reduction half-cell reaction.

 Then balance both the equations.

 Now determine the correct value of stoichiometry of H₂SO₄.

Oxidation half-reaction.

 $2I^{-}\rightarrow I_{2}+2e^{-}$  ..........(i)

 Here, I^-   is converted into I₂. The oxidation number of I is increasing from -1 to 0  hence, this is a type of oxidation reaction.

 Reduction half-reaction.

$6H^{+}+ClO_3^-+6e^{-}\rightarrow Cl^{-}+3H_{2}O$   ............(ii)

 Here, H₂O releases as a product. Hence , option (d) is correct.

 Mutiplying equation (i) by 3  and adding in equation (ii)

     $6I^{-}+ClO_3^-+6H^{+}\rightarrow Cl^{-}+3I_{2}+3H_{2}O$

 $6I^{-}+ClO_3^-+6H_{2}SO_{4}\rightarrow Cl^{-}+3I_{2}+3H_{2}O+6HSO_4^-$

 Stoichiormetric coefficient  of HSO₄^-  is  6

 Hence, option (a), (b) and (d)  are correct.