Which anion can undergo both oxidation and reduction? — p Block Elements Chemistry Question

💡 Solution & Explanation

Step 1: For an ion to undergo both oxidation and reduction (i.e., disproportionate or act as both an oxidizing and reducing agent), the central element must be in an intermediate oxidation state, rather than its maximum or minimum oxidation state. Step 2: In Cr2O7^2-, Cr is in its maximum +6 state (only reduction possible). In NO3^-, N is in its maximum +5 state. In S^2-, S is in its minimum -2 state (only oxidation possible). In OCl^- (hypochlorite), Cl is in the +1 oxidation state, which is intermediate between its limits of -1 and +7. Step 3: Thus, OCl^- can undergo both oxidation (to ClO3^- or ClO4^-) and reduction (to Cl^-), making option (c) the correct choice.