* Hydrogen peroxide (H₂O₂) acts as an oxidizing agent. It will oxidize the ferrous ions (Fe²⁺) from ferrous ammonium sulfate to ferric ions (Fe³⁺).

* Ferric ions (Fe³⁺) react with potassium thiocyanate (KSCN) to form a blood-red colored complex ion. This complex ion is a highly recognizable reaction in chemistry, often used as a test for the presence of iron.

The overall reaction can be summarized as:

Fe²⁺ + H₂O₂ → Fe³⁺ + H₂O

Fe³⁺ + SCN⁻ → [Fe(SCN)]²⁺ (red complex ion)

Therefore, the solution will turn red due to the formation of the ferric thiocyanate complex.