Chile saltpeter is a natural source of NaNO₃; it also contains NaIO₃. The NaIO₃ can be used as a source of iodine. Iodine is produced from sodium iodate in a two-step process occurring under acidic conditions:

IO₃^-(aq) + HSO₃^-(aq) → I^-(aq) + SO₄^2-(aq) (not balanced)

I^-(aq) + IO₃^-(aq) → I₂(s) + H₂O(l) (not balanced)

In the illustration, a 5.00 L sample of a NaIO₃(aq) solution containing 5.80 g NaIO₃/L is treated with the stoichiometric quantity of NaHSO₃ (no excess of either reactant). Then, a further quantity of the initial NaIO₃(aq) is added to the reaction mixture to bring about the second reaction. 

(a) How many grams of NaHSO₃ are required in the first step? 

(b) What additional volume of the starting solution must be added in the second step?

Transcribed Image Text:

-5.80 g NalO₂/L (b) ? L (a) ? g NaHSO3 5.00 L