2482 NTERNATIONAL STANDARD (Tso INTERNATIONAL ORGANIZATION FOR STANDARDIZATION MEKIYHAPOAHAN OPIAHI3AIIHI IO CTAHIAPTW3ALIHIH.ORGANISATION INTERNATIONALE DE NORMALISATION Sodium chloride for industrial use - Determination of calcium and magnesium contents - EDTA complexometric methods First edition - 1973-02-01 FE8 3 -- 1973 Asl lrternat Doc Sect UDC 661.833.321 : 546.41 : 546.46 : 543.24 Ref. No. ISO 2482-1973 (E) Descriptors : sodium chloride, chemical analysis, volumetric analysis, determination of content, calcium, magnesium. ISO Price based on 3 pages Copyright International Organization for Standardization ted without license from IHS Not for Resale FOREWORD ISO (the International Organization for Standardization) is a worldwide federation of national standards institutes (IsO Member Bodies). The work of developing International Standards is carried out through IsO Technical Committees. Every Member Body interested in a subject for which a Technical Committee has been set up has the right to be represented on that Committee. International organizations, governmental and non-governmental, in liaison with Iso, also take part in the work. Draft tnternational Standards adopted by the Technical Committees are circulated to the Member Bodies for approval before their acceptance as International Standards by the ISO Council. International Standard iso 2482 was drawn up by Technicail Committee ISO/TC 47, Chemistry. It was approved in January 1972by the Member Bodies of the following countries : Austria Ireland South Africa, Rep. of Belgium Italy Spain Korea, Dem.P.Rep. of Chile Switzerland Czechoslovakia Morocco Thailtand Egypt, Arab Rep. of Netheriands United Kingdom U.S.A. France New Zealand Poland U.S.S.R. Germany Hungary Portugal India Romania No Member Body expressed disapproval of the document. @ International Organization for Standardization, 1973 : Printed in Switzerland Copyright International Organization for Standardization ISO 2482-1973 (E) INTERNATIONAL STANDARD Sodium chloride for industrial use -- Determination of calcium and magnesium contents -- EDTA complexometric methods 5.1 Sodium hydroxide, p 1,08 g/ml, approximately 7,5 % 1SCOPE (m/m) solution or approximately 2 N. This International Standard specifies complexometric Dissolve 80 g of sodium hydroxide in water and dilute to methods for determining the calcium and magnesium contents in sodium chloride for industrial use. 1 000 ml. 5.2 Ethanol, 95 % (V/V). 2 FIELD OF APPLICATION Alcohol denatured with acetone, but not coloured, can also be used. 2.1 General case The method is applicable to the determination of 5.3 Triethanolamine, 25 % (V/V) solution. water-soluble caicium and magnesium, in sodium chloride Place 25 ml of triethanolamine in a 100 ml one-mark for industrial use, for calcium or magnesium contents volumetric flask, dilute to the mark and mix. greater than 0,001 % (m/m). 5.4 Buffer solution 2.2 Special case Dissolve 54 g of ammonium chloride in water. Add 350 ml Determination of calcium and magnesium in a principal of ammonia solution (p0,920 g/ml) and dilute to the mark in solution prepared in an acid medium. a 1 000 ml one-mark volumetric flask. adopted, related NOTE Whatever the conditions all determinations shall be carried out in the same medium, except the 5.5 Standard end-point matching solution determination of chlorides which shall always be carried out in an aqueous solution. Prepare this standard solution immediately before the determination (7.1.2). Pour 50 ml of water into a 250 ml conical flask followed by 2 mi of the triethanolamine 3 REFERENCE solution (5.3), 10 ml of the sodium hydroxide solution (5.1), 15 ml of ethanol (5.2) and 1,0 ml of the ISO 2479, Sodium chloride for industrial use glyoxal-bis-(2-hydroxyanil) solution (5.8). Determination of matter insoluble in water or acid and preparation of principal solutions for other determinations. 5.6 diSodium ethylenediaminetetra-acetate (EDTA), 0,02 M standard volumetric solution