Nitric Acid Oxidation of Silver

3Ag + 4HNO3(dilute) → 3AgNO3 + NO + 2H2O

Overview

Dilute nitric acid dissolves silver metal, oxidizing it to Ag⁺ while the nitrate is reduced to NO gas. Silver does not dissolve in HCl or H₂SO₄(dilute) because the H⁺ ion cannot oxidize silver, but nitric acid's nitrate ion provides sufficient oxidizing power. This is part of the aqua regia chemistry for noble metals.

Participants

Role Substance Coefficient State
Reactant Silver Ag 3 (s)
Reactant Nitric Acid HNO₃ 4 (aq)
Product Water H₂O 2 (l)
Product Silver Nitrate AgNO₃ 3 (aq)

Everyday Example

Jewelers use nitric acid to test whether a piece is real silver, as silver dissolves producing a green solution.

Industrial Importance

Silver dissolution in HNO₃ is the first step in silver refining and in preparing silver nitrate, a key photographic and analytical chemical.

Properties

Type
Redox
Reversible
No
Energy
Exothermic
ΔH
-85.0 kJ/mol

Related Reactions

Aqua Regia Dissolving Gold Bleaching with Sodium Hypochlorite Cerium(IV) Reduction by Iron(II) Chlorine Oxidation of Bromide Chromate-Dichromate Equilibrium Contact Process SO₂ Oxidation Copper Displaced by Iron Copper Oxidation by Nitric Acid Copper Patina Formation (Verdigris) Copper Reduction of Silver Ion

Frequently Asked Questions

What is the equation for Nitric Acid Oxidation of Silver?
The balanced equation is: 3Ag + 4HNO₃(dilute) → 3AgNO₃ + NO + 2H₂O.
What type of reaction is Nitric Acid Oxidation of Silver?
Nitric Acid Oxidation of Silver is a redox reaction.
Is Nitric Acid Oxidation of Silver exothermic or endothermic?
Nitric Acid Oxidation of Silver is exothermic (releases energy). The enthalpy change (ΔH) is -85.0 kJ/mol.