JAMB/WAEC Chemistry 2027 EP 88 - Balancing Redox Equations (Example 2) + Likely Exam Questions

JAMB/WAEC Chemistry – EP 88: Balancing Redox Equations (Example 2) + Likely Exam Questions & Solutions Welcome to Episode 88 of the O3Schools Chemistry Tutorial Series. In this lesson, we continue balancing redox equations using the oxidation number method. This approach is frequently tested in WAEC and occasionally in JAMB. What You Will Learn ✅ Advanced Redox Balancing ✅ Oxidation Number Method ✅ Step-by-Step Example ✅ Examination Shortcuts ✅ Likely JAMB/WAEC Questions Topics Covered • Redox Reactions • Oxidation Numbers • Balancing Equations • Oxidation • Reduction Example 2 Balance: Fe²⁺ + Cl₂ → Fe³⁺ + Cl⁻ Step 1: Assign Oxidation Numbers Fe²⁺ → Fe³⁺ Increase = +1 Oxidation Cl₂ → Cl⁻ 0 → -1 Decrease = 1 per chlorine atom Since Cl₂ contains 2 chlorine atoms: Total decrease = 2 Step 2: Equalize Changes Iron loses 1 electron. Chlorine gains 2 electrons. Multiply iron change by 2. 2Fe²⁺ + Cl₂ → 2Fe³⁺ + 2Cl⁻ Step 3: Check Balance Fe atoms: 2 = 2 Cl atoms: 2 = 2 Charge: Left = +4 Right = +4 Balanced. Final Balanced Equation 2Fe²⁺ + Cl₂ → 2Fe³⁺ + 2Cl⁻ Another Example Balance: Cu + Ag⁺ → Cu²⁺ + Ag Step 1 Cu: 0 → +2 Increase = 2 Ag⁺: +1 → 0 Decrease = 1 Step 2 Multiply silver by 2. Cu + 2Ag⁺ → Cu²⁺ + 2Ag Step 3 Check Charges Left = +2 Right = +2 Balanced. Examination Shortcut Write oxidation numbers. Determine increase and decrease. Equalize electron transfer. Balance atoms. Balance charges. Common Examination Errors ❌ Ignoring charge balance. ❌ Forgetting to multiply coefficients. ❌ Mixing oxidation with reduction. ❌ Incorrect oxidation numbers. Frequently Tested JAMB Areas 🔥 Oxidation Number Method 🔥 Electron Transfer 🔥 Fe²⁺ and Fe³⁺ 🔥 Halogens in Redox 🔥 Charge Balancing Likely Exam Questions 1. In Fe²⁺ → Fe³⁺, iron undergoes? A. Reduction B. Oxidation C. Hydrolysis D. Neutralization Answer: B 2. In Cl₂ → 2Cl⁻, chlorine undergoes? A. Oxidation B. Combustion C. Reduction D. Dissociation Answer: C 3. Which species acts as the oxidizing agent in the reaction? A. Fe²⁺ B. Fe³⁺ C. Cl₂ D. Cl⁻ Answer: C 4. Balance: Cu + Ag⁺ → Cu²⁺ + Ag A. Cu + Ag⁺ → Cu²⁺ + Ag B. Cu + 2Ag⁺ → Cu²⁺ + 2Ag C. 2Cu + Ag⁺ → 2Cu²⁺ + Ag D. Cu + Ag⁺ → 2Cu²⁺ + Ag Answer: B 5. Reduction is best defined as? A. Loss of electrons B. Increase in oxidation number C. Gain of electrons D. Addition of oxygen only Answer: C Quick Revision Note ✔ Oxidation = Increase in oxidation number. ✔ Reduction = Decrease in oxidation number. ✔ Electrons lost = Electrons gained. ✔ Total increase must equal total decrease. Why This Topic Is Important Understanding redox balancing helps students master: ✔ Electrochemistry ✔ Oxidation Numbers ✔ Chemical Equations ✔ Metal Reactions ✔ Industrial Chemistry Benefits of This Lesson ✔ Solve redox equations faster ✔ Master WAEC balancing techniques ✔ Improve Chemistry performance ✔ Build examination confidence About O3Schools O3Schools provides high-quality tutorials, CBT practice, likely examination questions, detailed solutions, and examination success strategies for JAMB, WAEC, NECO, and Post UTME candidates. Keywords JAMB Chemistry, WAEC Chemistry, Balancing Redox Equations, Oxidation Number Method, Electron Transfer, Oxidation, Reduction, Fe2+, Fe3+, Redox Reactions, Chemistry Tutorial, O3Schools Chemistry. #JAMBChemistry #WAECChemistry #RedoxEquations #BalancingRedoxEquations #OxidationNumbers #Oxidation #Reduction #ElectronTransfer #Electrochemistry #ChemistryTutorial #JAMBPastQuestions #O3Schools #StudySmart #ExamSuccess #NECOChemistry #ChemistryLessons