Acidified `KMnO_(4)`is decolourized by

Acidified KMnO_4 is decolourised by:

Acidified KMnO_(4) can be decolourised by:

Acidified KMnO_(4) can be decolourised by (a)_____.

Acidified KMnO_(4) solution is decolourised when

One litre of acidified KMnO_(4) solution containing 15.8g KMnO_(4) is decolourized by passing sufficient SO_(2) . If SO_(2) is produced by FeS_(2) , what is the amount of FeS_(2) required to give desired SO_(2) ?