Final answer:
The oxidizing agent in a redox reaction is the substance that accepts electrons and is reduced, while the reducing agent is the one that loses electrons and is oxidized. For instance, in the reaction MnO4- + SO2 → Mn2+ + SO42-, MnO4- is the oxidizing agent and SO2 is the reducing agent.
Step-by-step explanation:
Identifying Oxidizing and Reducing Agents in Redox Reactions
In redox reactions, the oxidizing agent is the substance that causes oxidation by accepting electrons and consequently is reduced. On the other hand, the reducing agent is the substance that causes reduction by losing electrons and is thereby oxidized. Let's consider the reaction MnO4- + SO2 → Mn2+ + SO42- as an example to identify the oxidizing and reducing agents. The manganese (Mn) in MnO4- is reduced as it gains electrons to form Mn2+. Consequently, MnO4- is the oxidizing agent. The sulfur (S) in SO2 is oxidized as it loses electrons to form SO42-, thus SO2 is the reducing agent.
The oxidation numbers of the atoms involved will change, indicating which species are being oxidized and reduced. In this example, the oxidation number of Mn decreases (from +7 to +2), while the oxidation number of S increases (from +4 to +6).