Question

Indicate whether each of the following statements is true or false: (a) If something is oxidized, it is formally losing electrons. (b) For the reaction \(\mathrm{Fe}^{3+}(a q)+\mathrm{Co}^{2+}(a q)-\cdots\) \(\mathrm{Fe}^{2+}(a q)+\mathrm{Co}^{3+}(a q), \mathrm{Fe}^{3+}(a q)\) is the reducing agent and \(\mathrm{Co}^{2+}(a q)\) is the oxidizing agent. (c) If there are no changes in the oxidation state of the reactants or products of a particular reaction, that reaction is not a redox reaction.

Short answer

(a) True (b) False (c) True

Step-by-step solution

Statement (a): Oxidation and Electron Loss

To determine if this statement is true or false, we need to recall the meaning of oxidation in a redox reaction. Oxidation is the process of losing electrons, while reduction is the process of gaining electrons. So, if something is oxidized, it is indeed formally losing electrons. Thus, statement (a) is true.

Statement (b): Identifying the Reducing and Oxidizing Agents

Given the redox reaction: \[\mathrm{Fe}^{3+}(a q)+\mathrm{Co}^{2+}(a q) \rightarrow \mathrm{Fe}^{2+}(a q)+\mathrm{Co}^{3+}(a q)\] We need to determine if \(\mathrm{Fe}^{3+}(a q)\) is the reducing agent and \(\mathrm{Co}^{2+}(a q)\) is the oxidizing agent. The reducing agent is the species that gets oxidized (loses electrons), while the oxidizing agent is the species that gets reduced (gains electrons). In this reaction, \(\mathrm{Fe}^{3+}\) is reduced to \(\mathrm{Fe}^{2+}\), and \(\mathrm{Co}^{2+}\) is oxidized to \(\mathrm{Co}^{3+}\). So, \(\mathrm{Fe}^{3+}(a q)\) is the oxidizing agent, and \(\mathrm{Co}^{2+}(a q)\) is the reducing agent. Therefore, statement (b) is false.

Statement (c): Redox Reactions and Changes in Oxidation State

This statement says that if there are no changes in the oxidation state of the reactants or products of a particular reaction, that reaction is not a redox reaction. Redox reactions are characterized by changes in oxidation states between reactants and products, as one species loses electrons while another species gains electrons. Therefore, if there are no changes in the oxidation states, it means that there is no electron transfer and the reaction is not a redox reaction. Thus, statement (c) is true.