One source of iodine is sodium iodate. Iodine is produced by a series of reactions. The first reaction is a reduction reaction with sodium hydrogen sulfite. IO₃^- (aq) + 3 HSO₃^- (aq) → I^- (aq) + 3 SO₄^2- (aq) + 3 H⁺ (aq)
5 I^-(aq) + IO₃^- (aq) + 6 H⁺ (aq) → 3 I₂(s) + 3 H₂O
How many grams of iodine are produced from 1.00 × 10² grams of NaHSO₃?

Question

Quizplus · Accepted Answer

1. Convert the given mass of NaHSO3 to moles:
m = 1.00 × 10^12 g
M = 104 g/mol
n = m/M = 9.62 × 10^9 mol NaHSO3

2. Use the stoichiometric coefficients to determine the number of moles of I2 produced:
2 mol NaHSO3 : 1 mol I2
1 mol NaIO3 : 5 mol I2

n(I2) = 9.62 × 10^9 mol NaHSO3 × (1 mol I2 / 2 mol NaHSO3) × (5 mol I2 / 1 mol NaIO3) = 2.40 × 10^10 mol I2

3. Convert the number of moles of I2 to grams:
m(I2) = n(I2) × M(I2) = 2.40 × 10^10 mol × 253.8 g/mol = 6.10 × 10^12 g = 48.8 g I2

One Source of Iodine Is Sodium Iodate