Determine the volume of 0.2 M K₂Cr₂O₇ solution required to react with 50 ml of 0.6 M FeSO₄ in acidic medium.
- 50 ml
- 25 ml
- 12.5 ml
- 100 ml
📝 Detailed explanation
Reaction: Cr₂O₇²⁻ + 6Fe²⁺ + 14H⁺ → 2Cr³⁺ + 6Fe³⁺ + 7H₂O.Moles Fe²⁺ = 0.05 × 0.6 = 0.03 mol.
Moles Cr₂O₇²⁻ = 0.03 / 6 = 0.005 mol.
Volume = 0.005 / 0.2 = 0.025 L = 25 ml.