Homework Help

Redox: Balance the equation SO_3^2+ + MnO_4^- ---> SO_4^2- + MnO_4^2-

user profile pic

spock11 | Student, Undergraduate | eNoter

Posted May 1, 2013 at 1:58 PM via web

dislike 1 like

Redox: Balance the equation

SO_3^2+ + MnO_4^- ---> SO_4^2- + MnO_4^2-

1 Answer | Add Yours

user profile pic

llltkl | College Teacher | Valedictorian

Posted May 1, 2013 at 3:39 PM (Answer #1)

dislike 1 like

The reaction occurs in basic medium. Also the first entry in the equation should be SO_3^2-.

Oxidation half reaction is:

SO_3^2- ---> SO_4^2- + 2e

Balancing oxygen atoms in basic medium,

SO_3^2- + 2OH˄- ---> SO_4^2- + H2O + 2e

Reduction half reaction is:

MnO_4^-  + e---> MnO_4^2-   × 2 (for electron balance)

2 MnO_4^-  + 2e---> 2MnO_4^2-

Adding the two parts and cancelling similar terms from both sides, the balanced chemical equation for the overall reaction is:

SO_3^2- + 2 MnO_4^-  + 2OH˄- ---> SO_4^2- + 2MnO_4^2- + H2O

Sources:

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes