Question

What number of electrons balances the charges in this half reaction

Answer 1

Answer : Two electrons balances the charges in this half reaction.

Explanation :

The given half reaction is,

$SO_2+2H_2O\rightarrow SO^{2-}_4+4H^+$

In this half reaction, there is no charges present on the left side of the reaction but on right side of the reaction, (2+) charge is present. So, two electrons (2-) are added on the right side of the reaction for balances the charge of the half reaction.

The balanced half reaction is,

$SO_2+2H_2O\rightarrow SO^{2-}_4+4H^++2e^-$

Hence, two electrons balances the charges in this half reaction.