, reacts quickly with halide sources to produce the insoluble silver halide, which is a cream precipitate if Br − Treatment of silver nitrate with base gives dark grey silver oxide: 2 AgNO 3 + 2 NaOH → Ag 2O + 2 NaNO 3 + H 2O Halide abstraction Similarly, silver nitrate is used to prepare some silver-based explosives, such as the fulminate, azide, or acetylide, through a precipitation reaction. When making photographic film, silver nitrate is treated with halide salts of sodium or potassium to form insoluble silver halide in situ in photographic gelatin, which is then applied to strips of tri- acetate or polyester. Treatment with solutions of halide ions gives a precipitate of AgX (X = Cl, Br, I). The nitrate can be easily replaced by other ligands, rendering AgNO 3 versatile. In addition, it is relatively stable to light, and it dissolves in numerous solvents, including water. It is non- hygroscopic, in contrast to silver fluoroborate and silver perchlorate. Silver nitrate is the least expensive salt of silver it offers several other advantages as well. Uses Precursor to other silver compounds Most metal nitrates thermally decompose to the respective oxides, but silver oxide decomposes at a lower temperature than silver nitrate, so the decomposition of silver nitrate yields elemental silver instead. Qualitatively, decomposition is negligible below the melting point, but becomes appreciable around 250 ☌ and fully decomposes at 440 ☌.
The silver nitrate reacts with copper to form hairlike crystals of silver metal and a blue solution of copper nitrate:Ģ AgNO 3(l) → 2 Ag(s) + O 2(g) + 2 NO 2(g) Ī typical reaction with silver nitrate is to suspend a rod of copper in a solution of silver nitrate and leave it for a few hours. The Ag-O distances range from 2.384 to 2.702 Å. Each Ag + center is bonded to six oxygen centers of both uni- and bidentate nitrate ligands. In the common orthorhombic form stable at ordinary temperature and pressure, the silver atoms form pairs with Ag-Ag contacts of 3.227 Å. The structure of silver nitrate has been examined by X-ray crystallography several times. The stoichiometry of the reaction depends upon the concentration of nitric acid used.ģ Ag + 4 HNO 3 (cold and diluted) → 3 AgNO 3 + 2 H 2O + NO Ag + 2 HNO 3 (hot and concentrated) → AgNO 3 + H 2O + NO 2 Indeed silver nitrate can be prepared by dissolving silver in nitric acid followed by evaporation of the solution. Synthesis and structure Īlbertus Magnus, in the 13th century, documented the ability of nitric acid to separate gold and silver by dissolving the silver. In solid silver nitrate, the silver ions are three- coordinated in a trigonal planar arrangement. It was once called lunar caustic because silver was called luna by ancient alchemists who associated silver with the moon. It is far less sensitive to light than the halides. It is a versatile precursor to many other silver compounds, such as those used in photography.
Silver nitrate is an inorganic compound with chemical formula AgNOģ. Crystals of silver nitrate under a microscope.
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