Final answer:
Silver (Ag) is the element undergoing reduction in the reaction Zn + 2AgNO₃, as it gains electrons forming precipitated silver metal.
Step-by-step explanation:
The element undergoing reduction in the reaction Zn + 2AgNO₃ is silver (Ag). The reaction, when using the chemical formulas provided, is not balanced and does not show all products, but the reducing agent can be inferred. In redox reactions, the reducing agent itself is oxidized. The reduction part of a redox reaction involves a species gaining electrons, and generally, the metal ion which forms a solid metal in the product side is the one being reduced. In this reaction, we would expect silver to precipitate out as silver metal (Ag). Combining the knowledge of redox reactions and the example equations given, the half-reaction for silver could look like this: Ag+(aq) + e− → Ag(s), showing that Ag+ is gaining an electron (reduction).