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

question 87

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. In one experiment, a student made up a reaction mixture which initially contained 0.0020 mol of iodate ions (IO₃^-) . If the iodate ions reacted completely, how many moles of thiosulfate ions (S₂O₃^2-) were needed in reaction 2, in order to react completely with the iodine (I₂) produced in reaction 1?

• A)0)0020 mol
• B)0)0030 mol
• C)0)0040 mol
• D)0)0050 mol
• E)0)0060 mol

---

Definitions:

Average Age

The mean age of a population, calculated by dividing the sum of all individual ages by the number of individuals.

Control Theory

A theory in sociology and criminology that explains individual compliance with social norms and laws through the presence of strong bonds with society that encourage self-control.

Deviant Behaviour

Actions or behaviors that violate societal norms or expectations, often drawing social condemnation or corrective measures.

Cultural Goals

Societal norms and values that dictate the aspirations and desirable achievements for its members, influencing behavior and social structure.