Observation of sodium sulfite solid added to a little alkaline potassium permanganate?
Well what did you see? The colour would dissipate certainly, but was there a brown precipitate? Did it go green..?
In acidic medium sulfite would be oxidized to sulfate, and permanganate reduced to
And of course permanganate reduced to
But this is in an ACID medium. In a basic medium, which was specified by the question, more likely the reduction product would be manganate ion,
For manganate ion....
...or MORE LIKELY.....
I am inclined to think that
The which is balanced with respect to mass and charge... Whew.
See here for another example of this process...