Question

Which ion can be both an oxidizing agent and reducing agent?

Answer 1

Answer: a)  Sn 2+  

Explanation:A reducing agent is a substance  that can be oxidized when it loses electrons while An oxidizing agent is a substance that is reduced when it gains   electrons.

 Considering  Cu 2+,   Fe 3+, Al 3+, Here,  Cu 2+ can  be reduce to its Copper metal, same for  Al 3+ to Aluminium  metal  and Fe 3+  to Fe 2+ ion  and will not be oxidized further since they are in their most oxidized states. The three ions are acting as only oxidizing agents.

while Sn 2+ can be oxidized to become Sn 4+ and also  be reduced to become Sn metal  acting as a reducing agent and an oxidizing agent.