Balancing Redox Reactions

Chemistry ⇒ Redox Reactions and Electrochemistry

Balancing Redox Reactions starts at 10 and continues till grade 12. QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Balancing Redox Reactions. How you perform is determined by your score and the time you take. When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.

See sample questions for grade 12

Balance the following redox reaction in acidic medium: Cr₂O₇²⁻ + C₂O₄²⁻ → Cr³⁺ + CO₂

Balance the following redox reaction in acidic medium: Cu + NO₃⁻ → Cu²⁺ + NO

Balance the following redox reaction in acidic medium: H₂O₂ + Cl₂O₇ → O₂ + HClO₄

Balance the following redox reaction in acidic medium: MnO₄⁻ + Fe²⁺ → Mn²⁺ + Fe³⁺

Balance the following redox reaction in basic medium: BrO₃⁻ + SO₃²⁻ → Br⁻ + SO₄²⁻

Balance the following redox reaction in basic medium: I₂ + S₂O₃²⁻ → I⁻ + S₄O₆²⁻

Balance the following redox reaction in basic medium: MnO₄⁻ + SO₃²⁻ → MnO₂ + SO₄²⁻

Balance the following redox reaction in basic medium: NO₂⁻ + Al → NH₃ + Al(OH)₄⁻

Which of the following is the correct balanced half-reaction for the oxidation of Fe²⁺ to Fe³⁺? (1) Fe²⁺ → Fe³⁺ + e⁻ (2) Fe²⁺ + e⁻ → Fe³⁺ (3) Fe²⁺ → Fe³⁺ + 2e⁻ (4) Fe²⁺ + 2e⁻ → Fe³⁺

Which of the following is the correct balanced half-reaction for the reduction of permanganate ion in acidic medium? (1) MnO₄⁻ + 8H⁺ + 5e⁻ → Mn²⁺ + 4H₂O (2) MnO₄⁻ + 4H⁺ + 2e⁻ → Mn²⁺ + 2H₂O (3) MnO₄⁻ + 8H⁺ + 2e⁻ → Mn²⁺ + 4H₂O (4) MnO₄⁻ + 5H⁺ + 5e⁻ → Mn²⁺ + 2H₂O

Which of the following is the correct balanced redox reaction for the reaction between Fe²⁺ and Cr₂O₇²⁻ in acidic medium? (1) 6Fe²⁺ + Cr₂O₇²⁻ + 14H⁺ → 6Fe³⁺ + 2Cr³⁺ + 7H₂O (2) 2Fe²⁺ + Cr₂O₇²⁻ + 14H⁺ → 2Fe³⁺ + 2Cr³⁺ + 7H₂O (3) 6Fe²⁺ + Cr₂O₇²⁻ + 7H⁺ → 6Fe³⁺ + 2Cr³⁺ + 7H₂O (4) 2Fe²⁺ + Cr₂O₇²⁻ + 7H⁺ → 2Fe³⁺ + 2Cr³⁺ + 7H₂O

Which of the following is the correct balanced redox reaction for the reaction between H₂O₂ and I⁻ in acidic medium? (1) H₂O₂ + 2I⁻ + 2H⁺ → I₂ + 2H₂O (2) H₂O₂ + I⁻ + 2H⁺ → I₂ + 2H₂O (3) 2H₂O₂ + 2I⁻ + 2H⁺ → I₂ + 4H₂O (4) H₂O₂ + 2I⁻ + H⁺ → I₂ + 2H₂O

Fill in the blank: In basic medium, after balancing the redox reaction in acidic medium, _______ ions are added to both sides to neutralize H⁺ ions.

Fill in the blank: In the half-reaction method, after balancing atoms and charges, the two half-reactions are _______ together to give the overall balanced equation.

Fill in the blank: In the reaction 2Fe³⁺ + 2I⁻ → 2Fe²⁺ + I₂, the species that is reduced is _______.

Fill in the blank: In the reaction 2H₂ + O₂ → 2H₂O, the element _______ is reduced.

True or False: In a redox reaction, the substance that is reduced acts as the oxidizing agent.

True or False: In balancing redox reactions in basic medium, you must add OH⁻ ions to both sides after balancing in acidic medium.

True or False: In basic medium, H⁺ ions are neutralized by adding OH⁻ ions to both sides of the equation.

True or False: The oxidation number of an element in its elemental form is always zero.