The Iodine "Clock Reaction" Involves the Following Sequence of Reactions

question 7

Multiple Choice

The iodine "clock reaction" involves the following sequence of reactions occurring in a reaction mixture in a single beaker.
1) IO₃^-(aq) + 5I^-(aq) + 6H⁺(aq)  3I₂(aq) + 3H₂O(l)
2) I₂(aq) + 2S₂O₃^2-(aq)  2I^-(aq) + S₄O₆^2-(aq)
The molecular iodine (I₂) formed in reaction 1 is immediately used up in reaction 2, so that no iodine accumulates. What is the overall reaction occurring in this experiment?

• A)IO₃^-(aq) + 3I^-(aq) + 2S₂O₃^2-(aq) + 6H⁺(aq)  2I₂(aq) + S₄O₆^2-(aq) + 3H₂O(l)
• B)IO₃^-(aq) + 4S₂O₃^2-(aq) + 6H⁺(aq)  I^-(aq) + 2S₄O₆^2-(aq) + 3H₂O(l)
• C)IO₃^-(aq) + 6S₂O₃^2-(aq) + 6H⁺(aq)  I^-(aq) + 3S₄O₆^2-(aq) + 3H₂O(l)
• D)IO₃^-(aq) + I₂(aq) + 8S₂O₃^2-(aq) + 6H⁺(aq)  3I^-(aq) + 4S₄O₆^2-(aq) + 3H₂O(l)
• E)IO₃^-(aq) + 2I₂(aq) + 6S₂O₃^2-(aq) + 6H⁺(aq)  5I^-(aq) + 3S₄O₆^2-(aq) + 3H₂O(l)

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Proton-decoupled

A technique in NMR spectroscopy where the interaction between protons is removed or decoupled, simplifying the spectrum and focusing on other interactions.

NMR Spectrum

A representation of the nuclear magnetic resonance of a molecule, providing detailed information about the structure, dynamics, reaction state, and chemical environment of molecules.

Signals

In spectroscopy, indications or peaks that represent the interaction of energy with matter, used to identify or quantify materials.