CBSE Class 10 Answered

Being a typical acid, nitric acid reacts with alkalis, basic oxides, and carbonates to form salts, such as ammonium nitrate. Due to its oxidizing nature, nitric acid generally does not donate its proton (that is, it does not liberate hydrogen) on reaction with metals and the resulting salts are usually in the higher oxidized states. For this reason, heavy corrosion can be expected and should be guarded against by the appropriate use of corrosion resistant metals or alloys.

Nitric acid has an acid dissociation constant (pK_a) of −1.4: in aqueous solution, it almost completely (93% at 0.1 mol/L) ionizes into the nitrate ion NO₃⁻ and a hydrated proton, known as a hydronium ion, H₃O⁺.

HNO₃ + H₂O → H₃O⁺ + NO₃^-

Reaction with non-metallic elements, with the exception of silicon and halogens, usually oxidizes them to their highest oxidation states as acids with the formation of nitrogen dioxide for concentrated acid and nitrogen oxide for dilute acid.

C + 4HNO₃ → CO₂ + 4NO₂ + 2H₂O

3C + 4HNO₃ → 3CO₂ + 4NO + 2H₂O  reacting with H₂ is to be clarifed, where did you read it!