Question

The concentration of hypochlorite ion can be determined via a redox titration using I-(aq) as the titrant. The relevant half-reactions are given below.

2e- + I3- → 3I- Eo = +0.53 V
2e- + 2H2O + 2ClO- → Cl2 + 4OH-Eo = +0.89 V
At the equivalence point of the titration:

Answer 1

The concentration of hypochlorite ion (ClO-) is determined by redox titration using iodide ion (I-) as the titrant. Redox potentials indicate the oxidizing power of hypochlorite and the reducing property of heavier halide ions. At the equivalence point, all hypochlorite reacts, and the end point is detected by a color change.

Step-by-step explanation:

The question revolves around the determination of the concentration of hypochlorite ion (ClO-) by using a redox titration method where iodide ion (I-) is the titrant. The relevant redox half-reactions with their respective standard electrode potentials are given, which indicate that hypochlorite is an oxidizing agent and iodide acts as a reducing agent in this context.

The given reactions also show how chlorine can undergo disproportionation to form hypochlorous acid and chloride ion, and these species can engage in further reactions under certain conditions like exposure to sunlight. Additionally, the redox potentials provided suggest that heavier halide ions such as Cl-, Br-, and I- can act as reducing agents.