Silver® nitrate

The therapeutic effects of silver compounds, including silver nitrate, have been known for many centuries. Both the Greeks and Romans, for example, used aqueous solutions of silver nitrate to treat wounds and cuts. In 1881, the German physician Carl Crede (1819-1892) developed the practice of applying a 2 percent solution of silver nitrate to the eyes of newborn babies to prevent gonorrheal 

Silver nitrate. Red atoms are oxygen blue atom is nitrogen and turquoise atom is silver. Gray sticks indicate double bonds. P L I S H E R S RESOURCE GROUP 

Film speed numbers, such as ISO IOO or ISO 4000, correspond to the size of silver nitrate particles on the film. The finer the grain, the more detailed the image quality. 

Silver nitrate is not toxic to humans or other mammals. But it is toxic to fish and other aquatic organisms. For this reason, it should not be discarded in lakes and rivers. 

Silver nitrate is made by dissolving metallic silver in weak nitric acid. 

A list of General Abbreviations appears on the front Endpapers 

Cycloadditions. The electrophilic nature of AgN03 enables it to complex with alkynes and allenes, thus enabling intramolecular cycloadditions to proceed. For example, treatment of a series of phenolic keto-ynes (eq 7) with a catalytic amount of AgN03 in methanol promotes cycloaddition to the triple bond in high yield. Similarly, a-hydroxyallenes are rapidly converted to 2,5-dihydropyrans on treatment with AgN03/CaC03 in aq acetone (eq 8).31 

Coverage of the use of AgN03/Na0H for oxidation of alcohols, aldehydes, etc., has not been included in this section as this ostensively amounts to the use of silver(I) oxide. 

Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China 

Based on its ability to complex with alkenes and alkynes, an additional useful application of AgNOs is the impregnation upon adsorbents (silica gel, alumina, Amberlyst resin, Sephadex, etc.) and the use of the material for the so-called argentation chromatography.  

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Mercaptan sulfur NF M 07-022 ISO 3012 ASTM D 3227 Silver nitrate analysis... 

Thus, when titrating iodide with silver nitrate, coagulation occurs as soon as a slight excess of silver ion has been added (so that a point of zero charge has been surpassed). 

Addition of silver nitrate to a solution of a chloride in dilute nitric acid gives a white precipitate of silver chloride, AgCl, soluble in ammonia solution. This test may be used for gravimetric or volumetric estimation of chloride the silver chloride can be filtered off, dried and weighed, or the chloride titrated with standard silver nitrate using potassium chromate(VI) or fluorescein as indicator. 

Addition of silver nitrate to a solution of a bromide in nitric acid produces a cream-coloured precipitate of silver bromide, soluble in ammonia (but not so readily as silver chloride). The reaction may be used quantitatively, as for a chloride. 

Silver nitrate soJuiion No ppt. White ppt., soluble in dil. ammonia solution Cream ppt., soluble in cone, ammonia solution Yellow ppt.. almost insoluble in cone, ammonia solution... 

A compound of cobalt has the formula Co(NH3)jtCl. 0.500 g of it was dissolved in 50.00 cm M hydrochloric acid the excess acid required 40.00 cm M sodium hydroxide solution to neutralise it. Another 0.500 g portion of the compound was dissolved in water and allowed to react with excess silver nitrate solution. 0.575 g of silver chloride was precipitated. 

Three crystalline compounds, one violet, one pale green, and one deep green in colour, all have the molecular formula CrClj. 6H2O. When equal masses of the three compounds are separately treated with an excess of aqueous silver nitrate at room temperature, the masses of white precipitate produced are in the ratio 3 2 1. Suggest an explanation for these results. 

All the silver halides are sensitive to light, decomposing eventually to silver. In sunlight, silver chloride turns first violet and finally black. The use of these compounds in photography depends on this (see below). (All silver salts are, in fact, photosensitive—the neck of a silver nitrate bottle is black owing to a deposit of silver.)... 

Silver nitrate, the most common silver salt, is obtained by dissolving the metal in nitric acid ... 

In ammoniacal solution (in which the ion [AgfNHjlj]" is formed) it is readily reduced to silver (see above) by many organic compounds. The use of silver nitrate for marking clothes depends on its reduction by the material to black silver. The reduction also occurs even when the neutral solution comes in contact with the skin, and a black stain is left. Thus solid silver nitrate rubbed on the skin leaves a black deposit and so is used in surgery as a mild caustic—hence the old name for silver nitrate of lunar caustic. 

If ethyne is passed through an ammoniacal solution of silver nitrate, there is a white precipitate of silver dicarbide (cf. copperflH ... 

Silver nitrate is used extensively in qualitative and quantitative analysis. 

In the former, it gives precipitates with halides (except the fluoride), cyanides, thiocyanates, chromates(VI), phosphate(V), and most ions of organic acids. The silver salts of organic acids are obtained as white precipitates on adding silver nitrate to a neutral solution of the acid. These silver salts on ignition leave silver. When this reaction is carried out quantitatively, it provides a means of determining the basicity of the acid... 

Gravimetrically, silver nitrate is used to determine the chloride ion. 

Silver nitrate is used volumetrically to estimate chloride, bromide, cyanide and thiocyanate ions. Potassium chromate or fluorescein is used as an indicator. 

Note cautiously the characteristic odour of acetaldehyde which this solution possesses. Then with the solution carry out the following general tests for aldehydes described on p. 341 Test No. I (SchiflF s reagent). No. 3 (Action of sodium hydroxide). No. 4 (Reduction of ammoniacal silver nitrate). Finally perform the two special tests for acetaldehyde given on p. 344 (Nitroprusside test and the Iodoform reaction). 

Hydrolysis of Ethyl Bromide. Add -a few drops of pure freshly distilled ethyl bromide to 2-3 ml. of aqueous silver nitrate solution in a test-tube and shake. Only a faint opalescence of silver bromide should be formed. -Now carefully warm the mixture in a small Bunsen flame, with gentle shaking silver bromide soon appears as a white suspension which rapidly increases in quantity and becomes a heavy precipitate. The ethyl bromide is thus moderately stable in cold water, but rapidly hydrolysed by hot water. 

Add a few drops of the distillate to an aqueous silver nitrate solution containing some dilute nitric acid and warm gently no silver chloride should be precipitated, indicating the complete absence of unchanged acetyl chloride. 

The use of lead nitrate in place of silver nitrate is to be avoided, for the precipitated lead sulphide occludes most of the free acid. 

Give silver mirror with ammoniacal silver nitrate. 

Reduction of ammoniacal silver nitrate. Place about 5 ml. of AgNOj solution in a thoroughly clean test-tube, and add 2-3 drops of dil. NaOH solution. Add dil. ammonia solution, drop by drop, until the precipitated silver oxide is almost redissolved, then add 2 - 3 drops of formaldehyde or acetaldehyde. A silver mirror is formed. 

Reduction of ammoniacal silver nitrate. Add a few drops of a neutral solution of a formate to ammoniacal AgNO (see Test 4, p. 342). A silver mirror or more usually a grey precipitate of metallic sih er is produced on boiling. 

Reduction of ammoniacal silver nitrate. Add i drop of dil. NaOH solution to about 5 ml. of AgNO, solution, and add dil. NH solution drop by drop until the silver oxide is almost redissolved. Add AgNO, solution until a faint but permanent precipitate is obtained (see p.525). Then add 0 5 ml. of a neutral tartrate solution. Place the tube in warm water a silver mirror is formed in a few minutes. 

Action of silver nitrate. Acidify 2 ml. of aqueous AgNOj solution with dil. HNO3 and add the acid chloride drop by drop with shaking. Acetyl chloride and benzoyl chloride give a precipitate of AgCl. Filter, wash with water, and then with methylated spirit to remove any benzoic acid the AgCl remains. 

Reduction of ammoniacal silver nitrate. Place 2 ml. of dilute silver nitrate solution in a clean test-tube. Add 1 drop of NaOH solution and then add dil. ammonia drop by drop until the precipitate formed by the NaOH is just not redissolved. Now add 1-2 ml. of glucose solution and place the test-tube in a water-bath at 50-60° a silver mirror is produced in 1 - 2 minutes. 

Does not reduce ammoniacal silver nitrate or Fehling s solution. If, however, the sucrose solution is warmed for some time with the reagent in question, slight hydrolysis to glucose and fructose does take place and reduction then occurs occasionally samples of sucrose will rapidly give a silver mirror, presumably owing to impurities. 

Reduces ammoniacal silver nitrate, and Fehling s solution. 

Does not reduce ammoniacal silver nitrate or Fehling s solution, and does not form an osazone. 

Oxidation, (a) Ammoniacal silver nitrate. To a few ml. of ammoniacal AgNOj (preparation, p. 525), add a few drops of cold aqueous benzo quinone solution a silver mirror or (more generally) a dark precipitate of metallic silver is formed in the cold. 

Solution in aqueous NaaCOa reduces silver nitrate (Schiff s test). 

Aliphatic mono-halides, and aromatic hydrocarbons with halogen in side-chain, precipitate silver hdide on treatment with cold aqueous silver nitrate solution. 

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