2366 NTERNATIONAL STANDARD (tso INTERNATIONAL ORGANIZATION FOR STANDARDIZATION -MEKIYHAPOIHA OPTAHH3ALIM HIO CTAHJIAPTW3ALIYW·ORGANISATION INTERNATIONALE DE NORMALISATION Cryolite, natural and artificial -- Determination of sodium content - Flame emission and atomic absorption spectrophotometric methods Cryolithe naturelle et artificielle-Dosage du sodium-Methodes par spectrophotométrie de flamme (emission)etparabsorptionatomique First edition - 1974-11-01 OCT 3 1 1974 ANSI Internat Doc icct ISO 2366-1974 (E) UDC 661.8 : 553.634 : 546.33: 543.423 Ref. No. 1SO 2366-1974 (E) Descriptors:cryolite,chemical analysis,determination of content, sodium,flamephotometry,atomic absorption. Price based on 4 pages Not for Resale FOREWORD ISo (the Internationa! 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, aiso 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 StandardsbytheIsoCouncil. International Standard ISO 2366 was drawn up by Technical Committee ISO/TC 47, Chemistry, and circulated to the Member Bodies in November 1972. It has been approved by the Member Bodies of the following countries : Australia India Spain Austria Israel Sweden Belgium Italy Switzerland Bulgaria Netherlands Thailand Canada New Zealand Turkey Egypt, Arab Rep. of Poland United Kingdom France Portugal U.S.S.R. Germany Romania Hungary South Africa, Rep. of This International Standard has also been approved by the International Union of Pure and Applied Chemistry (IUPAC). No Member Body expressed disapproval of the document. @ International Organization for Standardization, 1974 : Printed in Switzerland ovided by IHS under license with ISO No reproduction or networking pemmited without license from IHS Not for Resale ISO2366-1974 (E) INTERNATIONAL STANDARD Cryolite, natural and artificial -- Determination of sodium content -- Flame emission and atomic absorption spectrophotometric methods 1SCOPE 5.3 Standard sodium solution corresponding to 1,00 g of sodium per litre. This International Standard specifies a flame emission spectrophotometric method and a flame atomic absorption Weigh, to the nearest 0,000 1 g, 3,089 2 g of anhydrous spectrophotometric method for the determination of the sodium suiphate, previousiy dried at about 120 °c and sodium content of natural and artificial cryolite. cooled in a desiccator. Place in a beaker of convenient capacity (250 mi, for example), dissolve in about 100 ml of 2 FIELDOFAPPLICATION water, add 10 ml of the hydrochloric acid solution (5.2), transfer the solution quantitatively to a 1 000 ml one-mark The methods are applicable as alternatives to the volumetric fiask, dilute to the mark and mix. determination of the sodium content of natural and Transfer the solution to a plastics bottie.1) artificial cryolite of normal composition, for which the molar ratio NaF/AlF3 is equal to about 3. 1 ml of this standard solution contains 1,00 mg of Na. 3 REFERENCE 5.4 Standard sodium solution corresponding to 0,100 g of ISO/R 1619, Cryolite (natural and artificial)- -Preparation sodium per litre. and storage of test samples. Place 50,0 ml of the standard sodium solution (5.3) in a 500 mi one-mark voiumetric flask, dilute to the mark and 4 PRINCIPLE mix. Dissolution of a test portion in hydrochioric acid and water 1 ml of this solution contains 0,100 mg of Na. afterattack by concentrated sulphuric acid. Prepare this solution at the time of use and transfer to a Flame emission spectrophotometric method : plastics bottie.1) Atomizati