(a) Consider the following half equations. SO3^2-+ H2O --> SO4^2- + 2H^+1 + 2e-
...and...
MnO4^- + 8H^+ + 5e- --> Mn^2+ + 4H2O

Combine these two equations to obtain the overall reaction of sulfite ions with manganate (VII) ions.
(2)

(b)Use the equation you have written in (a) to calculate the volume of 0.277 M manganate (VII) ions that are required to react completely with 20.0 mL of 0.451 M sulfite ions. (4)

-I just need to know how to get the answer-Thanks!