IEC_TR_62432-2006.pdf

TECHNICAL REPORT IEC TR 62432 First edition2006-03 The rH index in aqueous and aqueous-organic media Reference number IEC/TR 62432:2006(E)LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.Publication numbering As from 1 January 1997 all IEC publications are issued with a designation in the 60000 series.For example,IEC 34-1 is now referred to as IEC 60034-1.Consolidated editions The IEC is now publishing consolidated versions of its publications.For example,edition numbers 1.0,1.1 and 1.2 refer,respectively,to the base publication,the base publication incorporating amendment 1 and the base publication incorporating amendments 1 and 2.Further information on IEC publications The technical content of IEC publications is kept under constant review by the IEC,thus ensuring that the content reflects current technology.Information relating to this publication,including its validity,is available in the IEC Catalogue of publications(see below)in addition to new editions,amendments and corrigenda.Information on the subjects under consideration and work in progress undertaken by the technical committee which has prepared this publication,as well as the list of publications issued,is also available from the following:IEC Web Site(www.iec.ch)Catalogue of IEC publications The on-line catalogue on the IEC web site(www.iec.ch/searchpub)enables you to search by a variety of criteria including text searches,technical committees and date of publication.On-line information is also available on recently issued publications,withdrawn and replaced publications,as well as corrigenda.IEC Just Published This summary of recently issued publications(www.iec.ch/online_news/justpub)is also available by email.Please contact the Customer Service Centre(see below)for further information.Customer Service Centre If you have any questions regarding this publication or need further assistance,please contact the Customer Service Centre:Email:custserviec.ch Tel:+41 22 919 02 11 Fax:+41 22 919 03 00 LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.TECHNICAL REPORT IECTR 62432 First edition2006-03 The rH index in aqueous and aqueous-organic media PRICE CODE IEC 2006 Copyright-all rights reserved No part of this publication may be reproduced or utilized in any form or by any means,electronic or mechanical,including photocopying and microfilm,without permission in writing from the publisher.International Electrotechnical Commission,3,rue de Varemb,PO Box 131,CH-1211 Geneva 20,SwitzerlandTelephone:+41 22 919 02 11 Telefax:+41 22 919 03 00 E-mail:inmailiec.ch Web:www.iec.ch N For price,see current catalogueCommission Electrotechnique InternationaleInternational Electrotechnical Commission LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.2 TR 62432 IEC:2006(E)CONTENTS FOREWORD.3 INTRODUCTION.5 1 Scope.6 2 General principles.6 2.1 Redox couples,redox equilibria,redox potentials,redox systems.6 2.2 The rH value.7 2.3 rH Standards for use in water and aqueous-organic solvent mixtures.11 2.4 Electrodes for the operational rH cell.12 2.4.1 General.12 2.4.2 The glass electrode.12 2.4.3 The inert noble-metal electrode(Pt or Au).12 2.5 rH Scales in diverse solvents.12 2.6 Pourbaixs diagrams for the triad rH pH EO|R.13 3 Instrumentation.13 Bibliography.14 Figure 1 Pourbaixs diagram for the triad rH pH EO|R for some key redox systems.10 Table 1.6 Table 2 Some reference aqueous solutions proposed as rH-metric standards rHS 8,9 at 25 C and for the calibration of the redox electrode at EO|R.11 Table 3 Values of(EQHY EH+|H2)6 with corresponding rHS values,at various temperatures,valid for any solvent(water W,or aquo-organic mixture Z=W+S compatible with Quinhydrone)in non-alkaline solution.12 Table 4 Parallelisms between the aqueous pH-metric and rH-metric scales.11 LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.TR 62432 IEC:2006(E)3 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ THE rH INDEX IN AQUEOUS AND AQUEOUS-ORGANIC MEDIA FOREWORD 1)The International Electrotechnical Commission(IEC)is a worldwide organization for standardization comprising all national electrotechnical committees(IEC National Committees).The object of IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields.To this end and in addition to other activities,IEC publishes International Standards,Technical Specifications,Technical Reports,Publicly Available Specifications(PAS)and Guides(hereafter referred to as“IEC Publication(s)”).Their preparation is entrusted to technical committees;any IEC National Committee interested in the subject dealt with may participate in this preparatory work.International,governmental and non-governmental organizations liaising with the IEC also p