Question

What is occurring in the following unbalanced reaction: \(ClO_3^- \rightarrow ClO_2\)?

Select the correct answer below:

a) Chlorine is oxidized
b) Chlorine is reduced
c) Oxygen is oxidized
d) Oxygen is reduced

Answer 1

In the reaction ClO_3^- → ClO_2, chlorine is being reduced as its oxidation state decreases from +5 to +4.

Step-by-step explanation:

The unbalanced reaction ClO_3^- → ClO_2 involves a change in the oxidation state of chlorine, which can be deduced by looking at the number of oxygen atoms bonded to chlorine in each species. In ClO_3^-, the chlorine has an oxidation state of +5 (each oxygen is -2 and the overall charge is -1, so +5 for Cl to balance it out). In ClO_2, the chlorine has an oxidation state of +4 (each oxygen is -2 and there is no overall charge, so +4 for Cl to balance it out).

Since the oxidation state of chlorine is decreasing from +5 to +4, chlorine is being reduced in this reaction. There is no indication that oxygen is being oxidized or reduced since the oxidation state for oxygen remains the same in both species, at -2 per oxygen atom.