The effect of adding the ammonia is to lower this concentration still further. AT d and k. PS 2.2 . Silver chloride and silver iodide are both soluble in liquid ammonia, but silver iodide is insoluble in aqueous ammonia. The solubility of AgCl, AgBr and AgI in a dimethylsulfoxide solution of ammonium nitrate has been determined by a potentiometric method. GROUP 7: TESTING FOR HALIDE IONS 1. a) Silver fluoride is soluble in water, and so you wouldn't get a precipitate. in a 0.1 M NH 4 NO 3 solution.. The trend in solubility of the silver halides in ammonia. A solution in contact with one of the silver halide precipitates contains a very small concentration of dissolved silver ions. The silver halide solubility can be increased by addition of ammonia in appropriate concentrations, due to complex ion formation: Ag + (aq) + 2NH 3 (aq) <==> [Ag(NH 3) 2] + (aq) K f = 1.5 x 10 7. Silver halides are used in photographic film and photographic paper, including graphic art film and paper, where silver halide crystals in gelatin are coated on to a film base, glass or paper substrate.The gelatin is a vital part of the emulsion as the protective colloid of appropriate physical and chemical properties. I assume that aqueous ammonia was intended. Topic 4: Inorganic Chemistry and the Periodic Table. Abstract--The solubility of silver hyponitrite in aqueous ammonia has been measured over the range of concentrations 0.1-2 N NHs. c) Silver iodide. Topic 4B: The elements of Group 7 (halogens) The less soluble the silver halide, the greater the concentration of ammonia needed to dissolve the silver halide. At 25°C the solubility products in terms of molarities are 2 × 10 −10, 9 × 10 −11 and 3 × 10 −12 resp. The use of acidified silver nitrate solution to identify and distinguish between halide ions. Students should be able to explain why: silver nitrate solution is used to identify halide ions; the silver nitrate solution is acidified; ammonia solution is added. The results are compatible with the assumption that the predominant complex formed in low concentrations is Ag(NHs)2 +. The trend in solubility of the silver halides in ammonia. b) The acid reacts removes any other ions present which might cause a confusing precipitate. Edexcel Chemistry.