Calculate the moles of S₂O₃²⁻ that are consumed during the course of the reaction in Trial 1.
Trial 1:
Solution A:
Boiled deionized water: 4.0 mL
Buffer: 1.0 mL
0.3 M KI: 1.0 mL
0.02 M Na₂S₂O₃: 1.0 mL
Starch: 5 drops
Solution B:
0.1 M H₂O₂: 3.0 mL
In Trial 1, Solution A and B are mixed,
3I⁻(aq) + H₂O₂ + 2H₃O⁺(aq) → I3⁻(aq) + 4H₂O(l)
2S₂O₃²⁻(aq) + I₃-(aq) → 3I⁻(aq) + S₄O₆²⁻(aq)
