(ISO 5317 International Standard INTE RNATIONAL ORGANIZATION FOR STANDARDIZATION MEKAYHAPOAHAR OPTAHM3AUMR HO CTAHAAPTW3AUMM ORGANISATION INTE RNATIONALE DE NORMALISATION ATi Fertilizers - Determination of water-soluble potassium content - Preparation of the test solution Engrais -- Dosage du potassium soluble dans I'eau - Preparation de la solution d'essai First edition - 1983-05-01 UDC 631.8 : 543.721 : 546.32 Ref. No. ISO 5317-1983 (E) ISO 5317-1983 (E) Descriptors : fertilizers, chemical analysis, determination of content, potassium, dissolving. Price based on 1 page Copyright International Organization for Standardization Notfor Resal Foreword ISo (the International Organization for Standardization) is a worldwide federation of national standards bodies (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 authorized 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 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. International Standard ISO5317was developed by Technical.Committee ISO/TC 134 Fertilizers and soil conditioners, and was circulated to the member bodies in February 1982. It has been approved by the member bodies of the following countries : Austria India Poland Bulgaria Israel Portugal China Italy Romania Czechoslovakia Kenya South Africa, Rep. of Egypt, Arab Rep. of Korea, Rep. of Sri Lanka France Netherlands Thailand Germany, F.R. New Zealand United Kingdom Norway USSR Hungary The member body of the following country expressed disapproval of the document on technical grounds : USA @ International Organization for Standardization, 1983 Printed in Switzerland Copyright International Organization for Standardization ISO 5317-1983 (E) INTERNATIONAL STANDARD Fertilizers - Determination of water-soluble potassium content -- Preparation of the test solution 6 Procedure 1 Scope and field of application This International Standard specifies the reference method for 6.1 Test portion the preparation of test solutions of fertilizers for the subsequent determination of their water-soluble potassium contents. Weigh, to the nearest 0,001 g, 5 g of the prepared test sample (see clause 5). 2 Principle 6.2 Dissolution Boiling of a test portion with water. Transfer the test portion (6.1) to the flask (4.1) with 400 ml of water. 3 Reagent Bring to the boil and continue boiling for 30 min. Use only distilled water or water of equivalent purity. Cool the contents of the flask and transfer to the one-mark volumetric flask (4.2). Dilute to the mark, mix well and filter into a dry beaker. Discard the first 50 ml of filtrate. 4 Apparatus Ordinary laboratory apparatus, and Test report 7 The test report for the subsequent determination of the water- 4.1 Flat-bottomed flask, of capacity 750 mi. soluble potassium content shall include the following informa- tion relevant to the preparation of the test solution : 4.2 One-mark volumetric flask, of capacity 1 000 ml, complying with the requirements of Iso 10421), class B a) all the information necessary for the complete iden- (maximum permitted error : ± 0,80 ml). tification of the sample; b) a reference to this International Standard; Preparation of the test sample 5 c) any operations not specified in this International Stan- Pretreatment of test samples of fertilizers for the determination dard, or regarded as optional, as well as any incidents likely of potassium content will form the subject of a future Inter- to affect the results of the determination of water-solubie national Standard. potassium content. 1) Iso 1042, Laboratory glassware -- One-mark volumetric flasks. 1 Copyright International