Chemistry - Redox Reactions Question with Solution | TestHub
During titrations in aqueous solutions one mole of is used for complete oxidation of and respectively and separately. Pick up the correct statement(s) :
Options:(select one or more)
Answer:
Solution:
The oxidation state of Mn in KMnO₄ is +7.
In acidic medium, MnO₄⁻ is reduced to Mn²⁺ (gain of 5e⁻).
In neutral medium, MnO₄⁻ is reduced to MnO₂ (gain of 3e⁻).
In strong basic medium, MnO₄⁻ is reduced to MnO₄²⁻ (gain of 1e⁻).
For FeSO₄: Fe²⁺ -> Fe³⁺ + e⁻ (1e⁻ change)
For H₂C₂O₄: C₂O₄²⁻ -> 2CO₂ + 2e⁻ (2e⁻ change)
For FeC₂O₄: Fe²⁺ -> Fe³⁺ + e⁻ and C₂O₄²⁻ -> 2CO₂ + 2e⁻ (total 3e⁻ change)
Option A: 1 mole KMnO₄ (5e⁻) can oxidize 5 moles FeSO₄ (5 x 1e⁻ = 5e⁻) in acidic medium. Correct.
Option B: 1 mole KMnO₄ (5e⁻) can oxidize 5/3 moles FeC₂O₄ (5/3 x 3e⁻ = 5e⁻) in acidic medium. The option states 3/5 mole, which is incorrect.
Option C: 1 mole KMnO₄ (3e⁻ in neutral medium) can oxidize 1 mole FeC₂O₄ (3e⁻). Correct.
Option D: 1 mole KMnO₄ (1e⁻ in strong basic medium) can oxidize 0.5 mole H₂C₂O₄ (0.5 x 2e⁻ = 1e⁻). Correct.
