AIIMS 2019 Chemistry Oxidizing Agents MCQ Question

Option C is correct because it accurately reflects the behavior of potassium dichromate (K₂Cr₂O₇) as an oxidizing agent in acidic conditions, where it is converted from the chromate ion (CrO₄²⁻) to the dichromate ion (Cr₂O₇²⁻) in the presence of H⁺ ions, as shown in the reaction: 2CrO₄²⁻ + 2H⁺ → Cr₂O₇²⁻ + H₂O. Other options are not provided, but it is important to note that potassium dichromate is unstable in both acidic and basic environments, leading to its decomposition and loss of oxidizing properties, which could render any claims about its stability in those conditions incorrect. Understanding the stability and reactivity of potassium dichromate is crucial for its application in redox titrations.