7109 (ISO International Standard INTE RNATIONAL ORGANIZATION FOR STANDARDIZATIONMEXAYHAPOAHAR OPrAHM3ALMA HO CTAHAAPTW3ALMM+ORGANISATION INTE RNATIONALE DE NORMALISATION Ammonia solution for industrial use -- Determination of residue after evaporation at 105 °C - Gravimetric method Ammoniaque a usage industriel - Détermination du residu apres évaporation a 105 °C - Methode gravimetrique First edition --- 1985-06-01 UDC 661.51 : 543.21 : 543.714 Ref. No. 1SO 7109-1985 (E) (F) G86I-NL/ SI Descriptors : industrial products, chemical compounds, ammonia solution, tests, determination, chemical residues, evaporation, gravimetric analysis. Price based on.1 page Foreword ISo (the International Organization for Standardization) is a worldwide federation of national standards bodies (IsO member bodies). The work of preparing International Standards is normally carried out through iso technical committees. Each member the right to be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with Iso, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISo Council. They are approved in accordance with iSO procedures requiring at least 75 % approval by the member bodies voting. International Standard ISO 7109 was prepared by Technical Committee ISO/TC 47, Chemistry. International Organizationfor Standardization,1985 PrintedinSwitzerland INTERNATIONAL STANDARD ISO7109-1985 (E) Ammonia solution for industrial use -- Determination of residue after evaporation at 105 oC - Gravimetric method WARNING -- Carry out all the operations in a well-ventilated fume cupboard. Scope and field of application to a volume of about 40 ml. Wash the volumetric flask with two 10 ml portions of distilled water and add the washings to the This International Standard specifies a gravimetric method for dish. Continue the operation until all liquid has completely thedeterminationoftheresidueafterevaporationof ammonia evaporated. solution for industrial use. Removethedishfromthewaterbathandplaceitintheelectric The method is applicable to solutions containing not more than oven (4.2) maintained at 105 ± 2 °C, for at least 30 min. Allow 35 % (m/m) of ammonia. the dish containing the residue to cool in a desiccator and weigh to the nearest 0,000 1 g. 2 Reference 6 Expression of results ISo 758, Liquid chemical products for industrial use - Deter- mination of density at 20 oC. The residue after evaporation, expressed in milligrams per kilogram, is given by the formula Principle 3 m1 - mo × 106 Vo Evaporation of a test portion in a tared platinum dish; weighing of the residue after drying at 105 ± 2 oc. where mo is the mass, in grams, of the empty platinum dish; 4 Apparatus m1 is the mass, in grams, of the platinum dish and Ordinary laboratory apparatus and residue; 4.1 Platinum dish, diameter about 75 mm. V is the volume, in millilitres, of the test portion (5.1); 4.2 Electric oven, capable of being Q is the density, in grams per millitre, of the test sample, fmaintained at 105 ± 2 °C. determined in accordance with the method specified in iso 758. 5 Procedure 7 Test report 5.1 Test portion The test report shall include the following particulars: Fill a 500 ml one-mark volumetric flask to the mark with some a) an identification of the sample; of the laboratory sample. b) the reference of the method used; 5.2 Determination c) the results and the method of expression used; Weigh, to the nearest 0,000 1 g, the platinum dish (4.1) previously dried at 105 ± 2 oC and cooled in a desiccator. Pour d) any unusual features noted during the determination; some of the test portion (5.1) into the weighed platinum dish, and place on a bath of boiling water in a well-ventilated fume e) any operation not included in this International Stan cupboard. Carefully evaporate the solution, gradual