Formic acid is a reducing agent. Substantriate this statement with examples.

Explanation

Formic acid contains both an aldehyde as well as well as an acid group. Hence, like other aldehydes, formic acid can easily be oxidised and therefore acts as a strong reducing agents.

(i) Formic acid reduces Tollens reagent (ammonical silver nitrate solution) to metallic silver.
`HCOO^(-) + underset("(tollens reagent)")(2Ag^(+) + 3OH^(-)) to underset("silver mirror")(2Ag) + CO_3^(2-) + 2H_2O`
(ii) Formic acid reduces Fehlings solution. It reduces blue coloured cupric ions to red coloured cuprous ions.
`HCOO^(-) + underset(("fehlings solution"))(2Cu^(2+) + 5OH^(-)) to underset("red precipitate")(Cu_2O) + CO_3^(2-) + 3H_2O`