INTERNATIONAL STANDARD (ISO) 2832 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION MEKIYHAPOTHAH OPrAHH3ALIM IIO CTAHIAPTW3AIIHIH.ORGANISATION INTERNATIONALE DE NORMALISATION Sodium fluoride for industrial use -- Determination of moisture content First edition - 1973-12-15 DEC 1 11973 As IniornatDocSect UDC 661.833.321 : 543.71 Ref. No. ISO 2832-1973 (E) Descriptors : sodium fluorides, chemical analysis, determination of content, moisture content, gravimetric analysis. Price based on 1 page Not for Resale FOREWORD ISO (the International Organization for Standardization) is a worldwide federation of nationai standards institutes (ISO Member Bodies). The work of developing International Standards is carried out through ISO Technicai 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. Internationai organizations, governmental and non-governmental, in liaison with IsO, also take part in the work. Draft Internationai 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 2832 was drawn up by Technical Committee ISO/TC 47, Chemistry, and circulated to the Member Bodies in July 1972. It has been approved by the Member Bodies of the following countries : Australia India Romania Austria Ireland South Africa, Rep. of Belgium Israel Sweden Itaiy Switzerland Czechoslovakia Egypt, Arab Rep. of Netheriands Thailand France Turkey New Zealand Germany Poland United Kingdom Hungary Portugal U.S.S.R. This International Standard has also been approved by the International Union of Pure and Applied Chemistry (UIPAC). No Member Body expressed disapproval of the document. @ International Organization for Standardization, 1973 . Printed in Switzerland Copyright International Organization for Standardization Not for Resale INTERNATIONAL STANDARD ISO 2832-1973 (E) Sodium fluoride for industrial use -- Determination of moisture content 1 SCOPE AND FIELD OF APPLICATION temperature. Then weigh, to the nearest 0,001 g, into the tared weighing bottle, approximately 20 g of the crude test This International Standard specifies a gravimetric method sample prepared according to IsO . .'1). for the determination of the moisture content of sodium fluoride for industrial use. 5.2 Determination Place the uncovered weighing bottle, containing the test 2 REFERENCE portion, together with its lid, in the oven (4.2), controlled at 110 ± 2°C and maintain at this temperature for 2 h. ISO ..., Sodium fluoride for industrial use - Preparation Then remove the weighing bottle and its lid from the oven and storage of test samples. 1) and place them in a desiccator, without ciosing the weighing bottle completely. Weigh to the nearest 0,001 g, 3 PRINCIPLE after cooling to ambient temperature and closing the weighing bottie with its lid. Drying of a test portion for 2h at 110°c and determination of the loss of mass. 6 EXPRESSION OF RESULTS 4 APPARATUS The moisture content is given, as a percentage by mass, by Ordinary laboratory apparatus and the formula 100 4.1 Weighing bottle, shallow, approximately 45 mm in (m, -m2) x m,-mo diameter. where 4.2 Electric oven, ventilated by convection, capabie of being controlled at 110 ± 2 °c, fitted with a thermometer mo is the mass, in grams, of the weighing botte and its so located that its bulb is near the weighing bottle used lid; during the test. The readings of this thermometer are used m, is the mass, in grams, of the weighing bottie and its to regulate the oven heat and to bring it to the desired lid containing the test portion before drying; temperature. m2 is the mass, in grams, of the weighing bottie and its Before commencing any test, ascertain, by means of the lid containing the test portion after drying. thermometer, the difference between the maximum and minimum temperature of the oven during o