What is the oxidising agent in the following equation?
〖HAsO〗_2 (aq)+〖Sn〗^(2+) (aq)+H^+ (aq)→As(s)+〖Sn〗^(4+) (aq)+H_2 O(l)

• Reduction:
  HAsO₂ is reduced to As(s):
  HAsO₂ + 3H⁺ + 3e⁻ → As + 2H₂O

• Oxidation:
  Sn²⁺ is oxidized to Sn⁴⁺:
  Sn²⁺ → Sn⁴⁺ + 2e⁻

Electron Transfer:

• HAsO₂ gains electrons and is reduced to As(s).
• Sn²⁺ loses electrons and is oxidized to Sn⁴⁺.

Since HAsO₂ undergoes reduction by accepting electrons, it acts as the oxidizing agent.

Additional Information:

• Sn²⁺:
  It is the reducing agent, as it loses electrons.
• H⁺:
  It participates in the reaction but does not undergo oxidation or reduction directly.
• Sn⁴⁺:
  This is the product of oxidation, not an oxidizing agent.