Determine whether each reaction is a redox reaction. For each redox reaction, identify the oxidizing agent and the reducing agent. a. 4 Li(s) + O₂(g) → 2 Li₂O(s) b. Mg(s) + Fe²⁺(aq) → Mg²⁺(aq) + Fe(s)

Verified step by step guidance

1. Step 1: Identify the oxidation states of each element in the reactants and products for both reactions.
2. Step 2: For reaction (a), assign oxidation states: Li in Li(s) is 0, O in O2(g) is 0, Li in Li2O(s) is +1, and O in Li2O(s) is -2.
3. Step 3: For reaction (b), assign oxidation states: Mg in Mg(s) is 0, Fe in Fe2+(aq) is +2, Mg in Mg2+(aq) is +2, and Fe in Fe(s) is 0.
4. Step 4: Determine if there is a change in oxidation states for each reaction. If there is a change, it is a redox reaction.
5. Step 5: Identify the oxidizing and reducing agents: The substance that is reduced (gains electrons) is the oxidizing agent, and the substance that is oxidized (loses electrons) is the reducing agent.

Key Concepts

Redox Reactions

Redox reactions, or reduction-oxidation reactions, involve the transfer of electrons between two species. In these reactions, one species is oxidized (loses electrons) while another is reduced (gains electrons). Identifying these changes is crucial for determining the nature of the reaction and the roles of the reactants.

Oxidizing and Reducing Agents

The oxidizing agent is the substance that gains electrons and is reduced in the process, while the reducing agent is the substance that loses electrons and is oxidized. Understanding these roles helps in identifying which reactants facilitate the electron transfer in a redox reaction, thus clarifying the overall process.

Half-Reaction Method

The half-reaction method is a technique used to analyze redox reactions by separating the oxidation and reduction processes into two half-reactions. This method allows for a clearer understanding of electron transfer and helps in balancing the overall reaction, making it easier to identify the oxidizing and reducing agents.