Sodium dithionite, Na 2 S 2 O 4 , is an important reducing agent. One interesting use

Question:

Sodium dithionite, Na₂S₂O₄, is an important reducing agent. One interesting use is the reduction of chromate ion to insoluble chromium(III) hydroxide by dithionite ion, S₂O₄^2- in basic solution. Sulfite ion is another product. The chromate ion may be present in wastewater from a chromium-plating plant, for example. What mass of Na₂S₂O₄ is consumed in a reaction with 100.0 L of wastewater having [CrO₄^2-] = 0.0148 M?