Question

balance the redox reaction by oxidation number - MnO4- + SO2 gives mn2+ + so4²-​

Answer 1

Step-by-step explanation:

2MnO4 −+ 5SO2 + 2H2O \: → 2Mn2 + 5SO42− +4H+

Explanation :

In the half reaction method, the number of atoms in each half reaction and number of electrons should be balanced.

The half reactions in the acidic medium are :

• (1):MnO_4^- + 8H^+ +5e^- → Mn^{2+ } + 4H_2O

• (2): SO_2 + 2H_2O SO_4^{2-} + 4H^++2e^-

• (1): MnO4− +8H+ + 5e−→ Mn2 + +4H2O

• (2): SO2 + 2H2O → SO42− +4H+ +2e−

Now multiply the equation (1) by 2 and equation (2) by 5

and then added both equation,

we get the balanced redox reaction.

Thus, the balanced redox reaction will be,

• 2MnO_4^- +5SO_2 + 2H_2O → Mn^{2+} + 5SO_4^{2-} + 4H^+

• 2MnO4− + 5SO2 + 2H2O → 2Mn2 + +5SO42− +4H+

✅Hope it helps you ❗