SIST EN ISO 9455-6:2023
(Main)Soft soldering fluxes - Test methods - Part 6: Determination and detection of halide (excluding fluoride) content (ISO 9455-6:2022)
Soft soldering fluxes - Test methods - Part 6: Determination and detection of halide (excluding fluoride) content (ISO 9455-6:2022)
This document specifies three quantitative methods for the determination of the ionic halide (excluding
fluoride) content of soldering fluxes. Halides are calculated as chlorides. A useful qualitative test
method for the detection of ionic halides is also described.
Method A is a potentiometric titration method for the determination of halide (excluding fluoride)
content and is applicable to flux classes 1 and 2, defined in ISO 9454-1. This method, which is considered
the reference method for these fluxes, is suitable for halide contents generally within the range of
0,05 % mass fraction to 2 % mass fraction in the non-volatile matter of the flux.
Method B is a titration method for the determination of the total halide (excluding fluoride) content
of water-soluble fluxes. It is applicable to flux classes 2122 to 2124, 3112 to 3114 and 3212 to 3214, as
defined in ISO 9454-1.
Method C is a titration method for the determination of the halide (excluding fluoride) content of watersoluble fluxes containing phosphates and is applicable to flux class 331, as defined in ISO 9454-1.
Method D is a qualitative test, using silver chromate test paper, for the presence of ionic halides. The
technique can be used for all classes of flux.
Flussmittel zum Weichlöten - Prüfverfahren - Teil 6: Bestimmung und Nachweis des Halogenidgehaltes (außer Fluorid) (ISO 9455-6:2022)
Dieses Dokument legt drei quantitative Methoden zur Bestimmung des Gehaltes ionischer Halogenide (außer
Fluorid) eines Weichlötflussmittels fest. Die Halogenide werden als Chlorid berechnet. Ebenso wird eine
brauchbare qualitative Prüfmethode zum Nachweis von ionischen Halogeniden beschrieben.
Methode A ist eine potentiometrische Titration zur Bestimmung des Halogenidgehaltes (außer Fluorid) und
ist anwendbar auf Flussmittel der Klassen 1 und 2 nach ISO 9454-1. Diese Methode dient als Referenzmethode
für diese Flussmittel und ist geeignet für Halogenidgehalte im Bereich von 0,05 % Massenanteil bis 2 % Massenanteil
des nichtflüchtigen Bestandteiles des Flussmittels.
Methode B ist eine Titrationsmethode zur Bestimmung des Gesamthalogenidgehaltes (außer Fluorid) wasserlöslicher
Flussmittel, anwendbar für Flussmittel der Klassen 2122 bis 2124, 3112 bis 3114 und 3212 bis 3214
nach ISO 9454-1.
Methode C ist eine Titrationsmethode zur Bestimmung des Halogenidgehaltes (außer Fluorid) wasserlöslicher
Flussmittel, die Phosphate enthalten, und ist anwendbar für Flussmittel der Klasse 331, nach ISO 9454-1.
Methode D ist eine qualitative Prüfung, die mit Silberchromatpapier durchgeführt wird und die Anwesenheit
von ionischen Halogeniden anzeigt. Dieses Verfahren kann für alle Flussmittelklassen angewandt werden.
Flux de brasage tendre - Méthodes d'essai - Partie 6: Dosage et détection des halogénures (à l'exception des fluorures) (ISO 9455-6:2022)
La présente partie de l'ISO 9455 prescrit trois méthodes quantitatives pour le dosage des halogénures ioniques (à l'exception des fluorures) dans les flux de brasage tendre. Les teneurs en halogénures sont calculées sous la forme de teneurs en chlorures. Une méthode d'essai qualitative utilisable pour la détection des halogénures ioniques est également décrite. La méthode A est une méthode de titrage potentiométrique pour le dosage des halogénures (à l'exception des fluorures). Elle est applicable aux flux de classes 1 et 2 tels que définis dans l'ISO 9454-1. Cette méthode, qui doit être considérée comme la méthode de référence pour ces flux, convient pour des teneurs en halogénures généralement comprises entre 0,05 % (m/m) et 2 % (m/m) dans les matières non volatiles du flux. La méthode B est une méthode de titrage pour le dosage total des halogénures (à l'exception des fluorures) dans les flux solubles dans l'eau. Elle est applicable aux flux de classes 2.1.2.A et 3.1.1.A tels que définis dans l'ISO 9454-1. La méthode C est une méthode de titrage pour le dosage des halogénures (à l'exception des fluorures) dans les flux solubles dans l'eau et contenant des phosphates. Elle est applicable aux flux de classe 3.2.1.A tels que définis dans l'ISO 9454-1. La méthode D est un essai qualitatif, utilisant du papier réactif au chromate d'argent, pour détecter la présence d'halogénures ioniques. Cette méthode est applicable à 48 toutes les classes de flux.
Talila za mehko spajkanje - Preskusne metode - 6. del: Določevanje in detekcija halogenida (razen fluorida) (ISO 9455-6:2022)
Ta dokument določa tri kvantitativne metode za določevanje ionskega halida (razen fluorida) v talilih za mehko spajkanje. Halidi se izračunajo kot kloridi. Opisana je tudi uporabna kvalitativna preskusna metoda za določevanje ionskih halidov. Metoda A je potenciometrična titracijska metoda za določevanje halida (razen fluorida) ter se uporablja za razreda talil 1 in 2, kot je opredeljeno v standardu ISO 9454-1. Ta metoda se obravnava kot referenčna metoda za ta talila in je primerna za halide običajno v razponu 0,05 % do 2 % masnega deleža v nehlapni snovi talila. Metoda B je titracijska metoda za določevanje skupnega halida (razen fluorida) v vodi topnih topil. Uporablja se za razrede talil 2122 do 2124, 3112 do 3114 in 3212 do 3214, opredeljene v standardu ISO 9454-1. Metoda C je titracijska metoda za določevanje halida (razen fluorida) v vodi topnih topil, ki vsebujejo fosfate, in se uporablja za razred talil 331, kot je opredeljeno v standardu ISO 9454-1. Metoda D je kvalitativni preskus, pri katerem se prisotnost ionskih halidov določi s preskusnim papirjem s srebrovim kromatom. Tehniko je mogoče uporabiti za vse razrede talil.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 9455-6:2023
01-marec-2023
Nadomešča:
SIST EN ISO 9455-6:2001
Talila za mehko spajkanje - Preskusne metode - 6. del: Določevanje in detekcija
halogenida (razen fluorida) (ISO 9455-6:2022)
Soft soldering fluxes - Test methods - Part 6: Determination and detection of halide
(excluding fluoride) content (ISO 9455-6:2022)
Flussmittel zum Weichlöten - Prüfverfahren - Teil 6: Bestimmung und Nachweis des
Halogenidgehaltes (außer Fluorid) (ISO 9455-6:2022)
Flux de brasage tendre - Méthodes d'essai - Partie 6: Dosage et détection des
halogénures (à l'exception des fluorures) (ISO 9455-6:2022)
Ta slovenski standard je istoveten z: EN ISO 9455-6:2022
ICS:
25.160.50 Trdo in mehko lotanje Brazing and soldering
SIST EN ISO 9455-6:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 9455-6:2023
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SIST EN ISO 9455-6:2023
EN ISO 9455-6
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2022
EUROPÄISCHE NORM
ICS 25.160.50 Supersedes EN ISO 9455-6:1997
English Version
Soft soldering fluxes - Test methods - Part 6:
Determination and detection of halide (excluding fluoride)
content (ISO 9455-6:2022)
Flux de brasage tendre - Méthodes d'essai - Partie 6: Flussmittel zum Weichlöten - Prüfverfahren - Teil 6:
Dosage et détection des halogénures (à l'exception des Bestimmung und Nachweis des Halogenidgehaltes
fluorures) (ISO 9455-6:2022) (außer Fluorid) (ISO 9455-6:2022)
This European Standard was approved by CEN on 29 November 2022.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 9455-6:2022 E
worldwide for CEN national Members.
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SIST EN ISO 9455-6:2023
EN ISO 9455-6:2022 (E)
Contents Page
European foreword . 3
2
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SIST EN ISO 9455-6:2023
EN ISO 9455-6:2022 (E)
European foreword
This document (EN ISO 9455-6:2022) has been prepared by Technical Committee ISO/TC 44 "Welding
and allied processes" in collaboration with Technical Committee CEN/TC 121 “Welding and allied
processes” the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by June 2023, and conflicting national standards shall be
withdrawn at the latest by June 2023.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 9455-6:1997.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 9455-6:2022 has been approved by CEN as EN ISO 9455-6:2022 without any
modification.
3
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SIST EN ISO 9455-6:2023
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SIST EN ISO 9455-6:2023
INTERNATIONAL ISO
STANDARD 9455-6
Second edition
2022-12
Soft soldering fluxes — Test
methods —
Part 6:
Determination and detection of halide
(excluding fluoride) content
Flux de brasage tendre — Méthodes d'essai —
Partie 6: Dosage et détection des halogénures (à l'exception des
fluorures)
Reference number
ISO 9455-6:2022(E)
© ISO 2022
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SIST EN ISO 9455-6:2023
ISO 9455-6:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
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SIST EN ISO 9455-6:2023
ISO 9455-6:2022(E)
Contents Page
Foreword .iv
1 S c op e . 1
2 N ormative references . 1
3 T erms and definitions . 1
4 M ethod A: Potentiometric method (Reference method) . 1
4 .1 P r i nc iple . 1
4. 2 R e a gent s . 2
4 . 3 A pp a r at u s . 2
4 .4 P r o c e du r e . 2
4.5 C alculation of results . 3
5 M ethod B: Titration method for halide (excluding fluoride) content of water-soluble
fluxes . 3
5 .1 P r i nc iple . 3
5 . 2 R e a g ent s . 4
5 . 3 A pp a r at u s . 4
5 .4 P r o c e du r e . 4
5.5 S tandardization of the ammonium thiocyanate solution (5.2.2) . 5
5.6 C alculation of results . 5
6 M ethod C: Titration method for the determination of halide (excluding fluoride)
content of water-soluble fluxes containing phosphates . 5
6 .1 P r i nc iple . 5
6 . 2 R e a g ent s . 6
6 . 3 A pp a r at u s . 6
6 .4 P r o c e du r e . 6
6.5 S tandardization of the ammonium thiocyanate solution (6.2.2) . 7
6.6 C alculation of results . 7
7 M ethod D: Qualitative test for the presence of ionic halides in flux .7
7.1 P r i nc iple . 7
7. 2 R e a g ent s . 7
7. 3 A pp a r at u s . 8
7.4 P r o c e du r e . 8
7.4.1 Preparation of flux test solution . 8
7.4 . 2 Te s t pr o c e du r e. 9
8 P r e c i s ion . 9
8.1 General . 9
8 . 2 Me t ho d A . 10
8 . 3 Me t ho d B . 10
8 .4 Me t ho d C . 10
9 T est report .10
Annex A (normative) Method for standardizing the silver nitrate solution .12
Bibliography .15
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SIST EN ISO 9455-6:2023
ISO 9455-6:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established 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.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 44, Welding and allied processes,
Subcommittee SC 12, Soldering materials, in collaboration with the European Committee for
Standardization (CEN) Technical Committee CEN/TC 121, Welding and allied processes, in accordance
with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 9455-6:1995), of which it constitutes a
minor revision. The changes are as follows:
— Clause 2 has been updated;
— new Clause 3, Terms and definitions, has been inserted;
— the coding of the fluxes has been updated in accordance with ISO 9454-1:2016;
— 4.2, 5.2, 6.2 and A.3 restructured;
— notes changed to body text in 4.4, 5.4, 5.6, 6.4 and 7.4.1.4;
— title added to Table 1;
— formulae numbered;
— minor editorial changes.
A list of all parts in the ISO 9455 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards
body. A complete listing of these bodies can be found at www.iso.org/members.html. Official
interpretations of ISO/TC 44 documents, where they exist, are available from this page:
https://committee.iso.org/sites/tc44/home/interpretation.html.
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SIST EN ISO 9455-6:2023
INTERNATIONAL STANDARD ISO 9455-6:2022(E)
Soft soldering fluxes — Test methods —
Part 6:
Determination and detection of halide (excluding fluoride)
content
1 S cope
This document specifies three quantitative methods for the determination of the ionic halide (excluding
fluoride) content of soldering fluxes. Halides are calculated as chlorides. A useful qualitative test
method for the detection of ionic halides is also described.
Method A is a potentiometric titration method for the determination of halide (excluding fluoride)
content and is applicable to flux classes 1 and 2, defined in ISO 9454-1. This method, which is considered
the reference method for these fluxes, is suitable for halide contents generally within the range of
0,05 % mass fraction to 2 % mass fraction in the non-volatile matter of the flux.
Method B is a titration method for the determination of the total halide (excluding fluoride) content
of water-soluble fluxes. It is applicable to flux classes 2122 to 2124, 3112 to 3114 and 3212 to 3214, as
defined in ISO 9454-1.
Method C is a titration method for the determination of the halide (excluding fluoride) content of water-
soluble fluxes containing phosphates and is applicable to flux class 331, as defined in ISO 9454-1.
Method D is a qualitative test, using silver chromate test paper, for the presence of ionic halides. The
technique can be used for all classes of flux.
2 Normat ive references
There are no normative references in this document.
3 T erms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Method A: Potentiometric method (Reference method)
4.1 Principle
A prepared, weighed sample of the flux is dissolved in a suitable solvent. The resulting solution is
titrated with standard silver nitrate solution, using a silver electrode, the mV readings being recorded
simultaneously. From the graph of volume of titrant readings against mV readings, the point of inflexion
is determined and the percentage halide content, expressed as chloride, is calculated. The method is not
suitable for the determination of fluoride.
This method is applicable to flux classes 1 and 2, as defined in ISO 9454-1.
1
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SIST EN ISO 9455-6:2023
ISO 9455-6:2022(E)
4.2 Reagents
Only reagents of recognized analytical quality and distilled or deionized water with a conductivity less
than 10 μS/cm are to be used.
4.2.1 Propan-2-ol.
4.2.2 Silver nitrate solution (0,02 mol/l).
3,4 g of silver nitrate (AgNO ) is dissolved in water then transferred to a 1-l volumetric flask and diluted
3
to the mark with water. It is mixed thoroughly. The silver nitrate (AgNO ) should be dried at (110 ± 5) °C
3
for 16 h and cooled in a desiccator before weighing.
Alternatively, a commercially available concentrate is used to prepare 0,02 mol/l standard silver nitrate
solution.
Standardize the silver nitrate solution using the method given in Annex A to derive the correlation
factor f . This is stored in an amber glass bottle.
1
NOTE 1 ml of silver nitrate solution is equivalent to 0,000 709 × f g of chloride ion.
1
4.3 A pparatus
The usual laboratory apparatus and, in particular, the following shall be used:
4.3.1 Millivolt meter.
4.3.2 Silver electrode.
4.3.3 Mercury/mercurous sulfate 1 mol/l sodium sulfate electrode, or a reversible hydrogen
electrode.
4.3.4 Magnetic or mechanical stirrer, with variable speed drive, the stirrer bar to be PTFE-coated.
4.4 Pr ocedure
Carry out the following procedure, in triplicate, on the flux sample.
Weigh, to the nearest 0,001 g, approximately 0,5 g of the solid flux sample or 2 g of the liquid flux sample,
avoiding loss of volatile matter during the weighing, and transfer it to a 250-ml low-form beaker.
This procedure is suitable for halide ion concentrations generally within the range of 0,1 % mass
fraction to 1 % mass fraction in the non-volatile content of the solution to be titrated. For flux samples
having halide ion concentrations outside this range, the sample mass taken should be adjusted, as
follows:
a) for flux samples having a halide ion concentration in the range of 0,05 % mass fraction to 0,1 %
mass fraction, the mass of sample taken should be double; and
b) for flux samples having a halide ion concentration in the range of 1 % mass fraction to 2 % mass
fraction, the mass of sample taken should be halved.
Add 100 ml of propan-2-ol (4.2.1), or water, according to the solubility characteristics of the flux. Cover
with a watch glass and allow to dissolve with gentle agitation.
For fluxes of class 12, as defined in ISO 9454-1, the choice of solvent should be agreed between the flux
manufacturer and the user.
2
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SIST EN ISO 9455-6:2023
ISO 9455-6:2022(E)
Place the beaker on the stand of the titration assembly with the electrodes, stirrer and burette in
position. Adjust the speed of the stirrer to give vigorous stirring without splashing. Titrate with the
silver nitrate solution (4.2.2), adding 1-ml portions and recording the mV meter readings after each
addition. As the end point is approached, reduce the additions of titrant to 0,1 ml and continue titrating
past the end point.
Plot the potential values against the volume of titrant added to obtain the titration curve. The point of
inflexion of the curve corresponds to the end point of the titration.
The point of inflexion of the curve may conveniently be determined by using the derivative curve.
Carry out a blank determination, using all reagents, for comparison purposes.
4.5 Calculation of r esults
The halide (excluding fluoride) content, expressed as the percentage by mass of chloride in the flux, is
given by Formula (1):
0, 070 9×V
f (1)
1
m
where
V is the volume, in ml, of silver nitrate solution used, less the volume needed to titrate the blank;
f is the correlation factor for the silver nitrate solution (see 4.2.2);
1
m is the mass, in g, of the sample taken.
The halide content of the flux sample is given by the mean of the three results obtained on the triplicate
test samples.
The halide content may also be expressed as the percentage by mass of chloride in the non-volatile
matter using Formula (2):
70, 9×V
f (2)
1
mS
where S is the percentage non-volatile matter content of the sample, determined as described in
ISO 9455-1 or ISO 9455-2. For solid flux samples, S = 100.
5 Method B: Titration method for halide (excluding fluoride) content of water-
soluble fluxes
5.1 Principle
A prepared sample of the flux is diluted to a known volume with water and a specified volume of sulfuric
acid of known concentration. The solution is then treated with a known quantity of silver nitrate
solution and the excess silver nitrate is titrated with ammonium thiocyanate. A blank determination
using water in place of the flux is carried out simultaneously and the percentage halide content,
expressed as chloride, is calculated. The method is not suitable for the determination of fluoride.
The test is applicable to fluxes of classes 2122 to 2124, 3112 to 3114 and 3212 to 3214 only, as defined
in ISO 9454-1.
Some liquid fluxes contain free hydrochloric acid and the halide content will consequently be greater
than the amount equivalent to the zinc and other chlorides present.
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SIST EN ISO 9455-6:2023
ISO 9455-6:2022(E)
5.2 Reagents
Only reagents of recognized analytical quality and distilled or deionized water with a conductivity less
than 10 μS/cm are to be used.
5.2.1 Silver nitrate solution (0,1 mol/l).
16,99 g of silver nitrate (AgNO ) is dissolved in water (see 4.2.2) then transferred to a 1-l volumetric
3
flask and diluted to the mark with water. This is mixed thoroughly. The silver nitrate (AgNO ) should be
3
dried at (110 ± 5) °C for 16 h and cooled in a desiccator before weighing.
Alternatively, a commercially available concentrate is used to prepare 0,1 mol/l standard silver nitrate
solution.
Standardize the silver nitrate solution using the method given in Annex A to derive the correlation
factor f . This is stored in an amber glass bottle.
2
NOTE 1 ml of silver nitrate solution is equivalent to 0,003 545 × f g of chloride ion.
2
5.2.2 Ammonium thiocyanate solution (approximately 0,1 mol/l).
8 g of ammonium thiocyanate (NH CNS) is dissolved in water then transferred to a 1-l volumetric flask
4
and diluted to the mark with water. This is mixed thoroughly.
Alternatively, a commercially available concentrate is used to prepare 0,1 mol/l standard ammonium
thiocyanate solution.
5.2.3 Sulfuric acid solution (20 % volume fraction). 200 ml of sulfuric acid (density 1,84 g/ml) is
cautiously added, with stirring, to 400 ml of water. It is then mixed, cooled, diluted to 1 l and mixed
thoroughly.
5.2.4 Ammonium ferric sulfate indicator solution.
10 g of ammonium ferric sulfate [NH Fe(SO ) ⋅ 12H O] is dissolved in 100 ml water.
4 4 2 2
5.2.5 Nitrobenzene.
WARNING — Care should be exercised in the handling and disposal of this hazardous reagent.
5.2.6 Nitric acid (density 1,42 g/ml).
5.3 A pparatus
Ordinary laboratory apparatus.
5.4 Pr ocedure
Carry out the following procedure, in triplicate, on the flux sample.
By means of a pipette, transfer 25 ml of the sample to a 500 ml volumetric flask. Add 10 ml of sulfuric
acid solution (5.2.3), dilute to the mark with water and mix.
By means of a pipette, transfer 10 ml of this solution to a glass-stoppered 500 ml conical flask and add
50 ml of water, followed by 5 ml of nitric acid (5.2.6).
To a similar flask transfer 60 ml of water and 5 ml of nitric acid (5.2.6) and carry out, simultaneously,
a blank determination following the same procedure and using the same quantities of reagents as used
for the flux sample.
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SIST EN ISO 9455-6:2023
ISO 9455-6:2022(E)
By means of a burette or a pipette, add 50 ml of silver nitrate solution (5.2.1) to the contents of the flask.
2 ml of nitrobenzene (5.2.5) may be added to assist coagulation of the precipitate.
Re-stopper the flask and shake it vigorously. Add 5 ml of ammonium ferric sulfate indicator solution
(5.2.4) and titrate with ammonium thiocyanate solution (5.2.1), shaking the flask vigorously between
additions of the titrant. The end point is indicated when a faint orange-red colour first persists
throughout the solution in the flask.
5.5 Standar dization of the ammonium thiocyanate solution (5.2.2)
Transfer 70 ml of water and 5 ml of nitric acid (5.2.6) to a 500 ml conical flask. By means of a pipette,
add 25 ml of silver nitrate solution (5.2.1). Add 5 ml of ammonium ferric sulfate indicator solution
(5.2.4) and titrate with the ammonium thiocyanate solution (5.2.2), as in the procedure given in 5.4.
Calculate the correlation factor f for the ammonium thiocyanate, as follows:
3
25× f
2
f =
3
volume of NH CNS
4
5.6 Calculation of r esults
The halide (excluding fluoride) content, expressed as the percentage by mass of chloride in the flux, is
given by Formula (3):
titret− itre ××0,003 545 f
()
blanksample 3
×100 (3)
05, d
which simplifies to:
0,709×V
f
3
d
where
is the volume, in ml, of ammonium thiocyanate solution (5.2.2) used in the titration of the blank,
V
minus the volume used in the titration of the flux sample;
d is the density, in g/ml, of the original flux sample, at 20 °C, determ
...
SLOVENSKI STANDARD
oSIST prEN ISO 9455-6:2022
01-oktober-2022
Talila za mehko spajkanje - Preskusne metode - 6. del: Določevanje in detekcija
halogenida (razen fluorida) (ISO/FDIS 9455-6:2022)
Soft soldering fluxes - Test methods - Part 6: Determination and detection of halide
(excluding fluoride) content (ISO/FDIS 9455-6:2022)
Flussmittel zum Weichlöten - Prüfverfahren - Teil 6: Bestimmung und Nachweis des
Halogenidgehaltes (außer Fluorid) (ISO/FDIS 9455-6:2022)
Flux de brasage tendre - Méthodes d'essai - Partie 6: Dosage et détection des
halogénures (à l'exception des fluorures) (ISO/FDIS 9455-6:2022)
Ta slovenski standard je istoveten z: prEN ISO 9455-6
ICS:
25.160.50 Trdo in mehko lotanje Brazing and soldering
oSIST prEN ISO 9455-6:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
oSIST prEN ISO 9455-6:2022
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oSIST prEN ISO 9455-6:2022
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 9455-6
ISO/TC 44/SC 12
Soft soldering fluxes — Test
Secretariat: DIN
methods —
Voting begins on:
2022-08-05
Part 6:
Voting terminates on:
Determination and detection of halide
2022-10-28
(excluding fluoride) content
Flux de brasage tendre — Méthodes d'essai —
Partie 6: Dosage et détection des halogénures (à l'exception des
fluorures)
ISO/CEN PARALLEL PROCESSING
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 9455-6:2022(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2022
---------------------- Page: 3 ----------------------
oSIST prEN ISO 9455-6:2022
ISO/FDIS 9455-6:2022(E)
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 9455-6
ISO/TC 44/SC 12
Soft soldering fluxes — Test
Secretariat: DIN
methods —
Voting begins on:
Part 6:
Voting terminates on:
Determination and detection of halide
(excluding fluoride) content
Flux de brasage tendre — Méthodes d'essai —
Partie 6: Dosage et détection des halogénures (à l'exception des
fluorures)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
ISO/CEN PARALLEL PROCESSING
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
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or ISO’s member body in the country of the requester.
RECIPIENTS OF THIS DRAFT ARE INVITED TO
ISO copyright office
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
CP 401 • Ch. de Blandonnet 8
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
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DOCUMENTATION.
Phone: +41 22 749 01 11
IN ADDITION TO THEIR EVALUATION AS
Reference number
Email: copyright@iso.org
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 9455-6:2022(E)
Website: www.iso.org
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
Published in Switzerland
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
ii
© ISO 2022 – All rights reserved
NATIONAL REGULATIONS. © ISO 2022
---------------------- Page: 4 ----------------------
oSIST prEN ISO 9455-6:2022
ISO/FDIS 9455-6:2022(E)
Contents Page
Foreword .iv
1 S c op e . 1
2 Nor m at i ve r ef er enc e s . 1
3 T erms and definitions . 1
4 M ethod A: Potentiometric method (Reference method) . 1
4 .1 P r i nc iple . 1
4. 2 R e a gent s . 2
4 . 3 A pp a r at u s . 2
4 .4 P r o c e du r e . 2
4.5 C alculation of results . 3
5 M ethod B: Titration method for halide (excluding fluoride) content of water-soluble
fluxes . 3
5 .1 P r i nc iple . 3
5 . 2 R e a g ent s . 4
5 . 3 A pp a r at u s . 4
5 .4 P r o c e du r e . 4
5.5 S tandardization of the ammonium thiocyanate solution (5.2.2) . 5
5.6 C alculation of results . 5
6 M ethod C: Titration method for the determination of halide (excluding fluoride)
content of water-soluble fluxes containing phosphates . 5
6 .1 P r i nc iple . 5
6 . 2 R e a g ent s . 6
6 . 3 A pp a r at u s . 6
6 .4 P r o c e du r e . 6
6.5 S tandardization of the ammonium thiocyanate solution (6.2.2) . 7
6.6 C alculation of results . 7
7 M ethod D: Qualitative test for the presence of ionic halides in flux .7
7.1 P r i nc iple . 7
7. 2 R e a g ent s . 8
7. 3 A pp a r at u s . 8
7.4 P r o c e du r e . 8
7.4.1 Preparation of flux test solution . 8
7.4 . 2 Te s t pr o c e du r e. 9
8 P r e c i s ion . 9
8 .1 G ener a l . 9
8 . 2 Me t ho d A . 10
8 . 3 Me t ho d B . 10
8 .4 Me t ho d C . 10
9 T est report .10
Annex A (normative) Method for standardizing the silver nitrate solution .12
Bibliography .15
iii
© ISO 2022 – All rights reserved
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oSIST prEN ISO 9455-6:2022
ISO/FDIS 9455-6:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established 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.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/
iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 44, Welding and allied processes,
Subcommittee SC 12, Soldering materials, in collaboration with the European Committee for
Standardization (CEN) Technical Committee CEN/TC 121, Welding and allied processes, in accordance
with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 9455-6:1995), of which it constitutes a
minor revision. The changes are as follows:
— Clause 2 has been updated;
— new Clause 3, Terms and definitions, has been inserted;
— the coding of the fluxes has been updated in accordance with ISO 9454-1:2016;
— 4.2, 5.2, 6.2 and A.3 restructured;
— notes changed to body text in 4.4, 5.4, 5.6, 6.4 and 7.4.1.4;
— title added to Table 1;
— formulae numbered;
— minor editorial changes.
A list of all parts in the ISO 9455 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html. Official interpretations of
ISO/TC 44 documents, where they exist, are available from this page: https://committee.iso.org/sites/
tc44/home/interpretation.html.
iv
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oSIST prEN ISO 9455-6:2022
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 9455-6:2022(E)
Soft soldering fluxes — Test methods —
Part 6:
Determination and detection of halide (excluding fluoride)
content
1 S cope
This document specifies three quantitative methods for the determination of the ionic halide (excluding
fluoride) content of soldering fluxes. Halides are calculated as chlorides. A useful qualitative test
method for the detection of ionic halides is also described.
Method A is a potentiometric titration method for the determination of halide (excluding fluoride)
content and is applicable to flux classes 1 and 2, defined in ISO 9454-1. This method, which is considered
the reference method for these fluxes, is suitable for halide contents generally within the range of
0,05 % mass fraction to 2 % mass fraction in the non-volatile matter of the flux.
Method B is a titration method for the determination of the total halide (excluding fluoride) content
of water-soluble fluxes. It is applicable to flux classes 2122 to 2124, 3112 to 3114 and 3212 to 3214, as
defined in ISO 9454-1.
Method C is a titration method for the determination of the halide (excluding fluoride) content of water-
soluble fluxes containing phosphates and is applicable to flux class 331, as defined in ISO 9454-1.
Method D is a qualitative test, using silver chromate test paper, for the presence of ionic halides. The
technique can be used for all classes of flux.
2 Normat ive references
There are no normative references in this document.
3 T erms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Method A: Potentiometric method (Reference method)
4.1 Principle
A prepared, weighed sample of the flux is dissolved in a suitable solvent. The resulting solution is
titrated with standard silver nitrate solution, using a silver electrode, the mV readings being recorded
simultaneously. From the graph of volume of titrant readings against mV readings, the point of inflexion
is determined and the percentage halide content, expressed as chloride, is calculated. The method is not
suitable for the determination of fluoride.
This method is applicable to flux classes 1 and 2, as defined in ISO 9454-1.
1
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oSIST prEN ISO 9455-6:2022
ISO/FDIS 9455-6:2022(E)
4.2 Reagents
Only reagents of recognized analytical quality and distilled or deionized water with a conductivity less
than 10 μS/cm are to be used.
4.2.1 Propan-2-ol.
4.2.2 Silver nitrate solution (0,02 mol/l).
3,4 g of silver nitrate (AgNO ) is dissolved in water then transferred to a 1-l volumetric flask and diluted
3
to the mark with water. It is mixed thoroughly. The silver nitrate (AgNO ) should be dried at (110 ± 5) °C
3
for 16 h and cooled in a desiccator before weighing.
Alternatively, a commercially available concentrate is used to prepare 0,02 mol/l standard silver nitrate
solution.
Standardize the silver nitrate solution using the method given in Annex A to derive the correlation
factor f . This is stored in an amber glass bottle.
1
NOTE 1 ml of silver nitrate solution is equivalent to 0,000 709 × f g of chloride ion.
1
4.3 A pparatus
The usual laboratory apparatus and, in particular, the following shall be used:
4.3.1 Millivolt meter.
4.3.2 Silver electrode.
4.3.3 Mercury/mercurous sulfate 1 mol/l sodium sulfate electrode, or a reversible hydrogen
electrode.
4.3.4 Magnetic or mechanical stirrer, with variable speed drive, the stirrer bar to be PTFE-coated.
4.4 Pr ocedure
Carry out the following procedure, in triplicate, on the flux sample.
Weigh, to the nearest 0,001 g, approximately 0,5 g of the solid flux sample or 2 g of the liquid flux sample,
avoiding loss of volatile matter during the weighing, and transfer it to a 250-ml low-form beaker.
This procedure is suitable for halide ion concentrations generally within the range of 0,1 % mass
fraction to 1 % mass fraction in the non-volatile content of the solution to be titrated. For flux samples
having halide ion concentrations outside this range, the sample mass taken should be adjusted, as
follows:
a) for flux samples having a halide ion concentration in the range of 0,05 % mass fraction to 0,1 %
mass fraction, the mass of sample taken should be double; and
b) for flux samples having a halide ion concentration in the range of 1 % mass fraction to 2 % mass
fraction, the mass of sample taken should be halved.
Add 100 ml of propan-2-ol (4.2.1), or water, according to the solubility characteristics of the flux. Cover
with a watch glass and allow to dissolve with gentle agitation.
For fluxes of class 12, as defined in ISO 9454-1, the choice of solvent should be agreed between the flux
manufacturer and the user.
2
© ISO 2022 – All rights reserved
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oSIST prEN ISO 9455-6:2022
ISO/FDIS 9455-6:2022(E)
Place the beaker on the stand of the titration assembly with the electrodes, stirrer and burette in
position. Adjust the speed of the stirrer to give vigorous stirring without splashing. Titrate with the
silver nitrate solution (4.2.2), adding 1-ml portions and recording the mV meter readings after each
addition. As the end point is approached, reduce the additions of titrant to 0,1 ml and continue titrating
past the end point.
Plot the potential values against the volume of titrant added to obtain the titration curve. The point of
inflexion of the curve corresponds to the end point of the titration.
The point of inflexion of the curve may conveniently be determined by using the derivative curve.
Carry out a blank determination, using all reagents, for comparison purposes.
4.5 Calculation of r esults
The halide (excluding fluoride) content, expressed as the percentage by mass of chloride in the flux, is
given by Formula (1):
0, 070 9×V
f (1)
1
m
where
V is the volume, in ml, of silver nitrate solution used, less the volume needed to titrate the blank;
is the correlation factor for the silver nitrate solution (see 4.2.2);
f
1
m is the mass, in g, of the sample taken.
The halide content of the flux sample is given by the mean of the three results obtained on the triplicate
test samples.
The halide content may also be expressed as the percentage by mass of chloride in the non-volatile
matter using Formula (2):
70, 9×V
f (2)
1
mS
where S is the percentage non-volatile matter content of the sample, determined as described in
ISO 9455-1 or ISO 9455-2. For solid flux samples, S = 100.
5 Method B: Titration method for halide (excluding fluoride) content of water-
soluble fluxes
5.1 Principle
A prepared sample of the flux is diluted to a known volume with water and a specified volume of sulfuric
acid of known concentration. The solution is then treated with a known quantity of silver nitrate
solution and the excess silver nitrate is titrated with ammonium thiocyanate. A blank determination
using water in place of the flux is carried out simultaneously and the percentage halide content,
expressed as chloride, is calculated. The method is not suitable for the determination of fluoride.
The test is applicable to fluxes of classes 2122 to 2124, 3112 to 3114 and 3212 to 3214 only, as defined
in ISO 9454-1.
Some liquid fluxes contain free hydrochloric acid and the halide content will consequently be greater
than the amount equivalent to the zinc and other chlorides present.
3
© ISO 2022 – All rights reserved
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oSIST prEN ISO 9455-6:2022
ISO/FDIS 9455-6:2022(E)
5.2 Reagents
Only reagents of recognized analytical quality and distilled or deionized water with a conductivity less
than 10 μS/cm are to be used.
5.2.1 Silver nitrate solution (0,1 mol/l).
16,99 g of silver nitrate (AgNO ) is dissolved in water (see 4.2.2) then transferred to a 1-l volumetric
3
flask and diluted to the mark with water. This is mixed thoroughly. The silver nitrate (AgNO ) should be
3
dried at (110 ± 5) °C for 16 h and cooled in a desiccator before weighing.
Alternatively, a commercially available concentrate is used to prepare 0,1 mol/l standard silver nitrate
solution.
Standardize the silver nitrate solution using the method given in Annex A to derive the correlation
factor f . This is stored in an amber glass bottle.
2
NOTE 1 ml of silver nitrate solution is equivalent to 0,003 545 × f g of chloride ion.
2
5.2.2 Ammonium thiocyanate solution (approximately 0,1 mol/l).
8 g of ammonium thiocyanate (NH CNS) is dissolved in water then transferred to a 1-l volumetric flask
4
and diluted to the mark with water. This is mixed thoroughly.
Alternatively, a commercially available concentrate is used to prepare 0,1 mol/l standard ammonium
thiocyanate solution.
5.2.3 Sulfuric acid solution (20 % volume fraction). 200 ml of sulfuric acid (density 1,84 g/ml) is
cautiously added, with stirring, to 400 ml of water. It is then mixed, cooled, diluted to 1 l and mixed
thoroughly.
5.2.4 Ammonium ferric sulfate indicator solution.
10 g of ammonium ferric sulfate [NH Fe(SO ) ⋅ 12H O] is dissolved in 100 ml water.
4 4 2 2
5.2.5 Nitrobenzene.
WARNING — Care should be exercised in the handling and disposal of this hazardous reagent.
5.2.6 Nitric acid (density 1,42 g/ml).
5.3 A pparatus
Ordinary laboratory apparatus.
5.4 Pr ocedure
Carry out the following procedure, in triplicate, on the flux sample.
By means of a pipette, transfer 25 ml of the sample to a 500 ml volumetric flask. Add 10 ml of sulfuric
acid solution (5.2.3), dilute to the mark with water and mix.
By means of a pipette, transfer 10 ml of this solution to a glass-stoppered 500 ml conical flask and add
50 ml of water, followed by 5 ml of nitric acid (5.2.6).
To a similar flask transfer 60 ml of water and 5 ml of nitric acid (5.2.6) and carry out, simultaneously,
a blank determination following the same procedure and using the same quantities of reagents as used
for the flux sample.
4
© ISO 2022 – All rights reserved
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oSIST prEN ISO 9455-6:2022
ISO/FDIS 9455-6:2022(E)
By means of a burette or a pipette, add 50 ml of silver nitrate solution (5.2.1) to the contents of the flask.
2 ml of nitrobenzene (5.2.5) may be added to assist coagulation of the precipitate.
Re-stopper the flask and shake it vigorously. Add 5 ml of ammonium ferric sulfate indicator solution
(5.2.4) and titrate with ammonium thiocyanate solution (5.2.1), shaking the flask vigorously between
additions of the titrant. The end point is indicated when a faint orange-red colour first persists
throughout the solution in the flask.
5.5 Standar dization of the ammonium thiocyanate solution (5.2.2)
Transfer 70 ml of water and 5 ml of nitric acid (5.2.6) to a 500 ml conical flask. By means of a pipette,
add 25 ml of silver nitrate solution (5.2.1). Add 5 ml of ammonium ferric sulfate indicator solution
(5.2.4) and titrate with the ammonium thiocyanate solution (5.2.2), as in the procedure given in 5.4.
Calculate the correlation factor f for the ammonium thiocyanate, as follows:
3
25× f
2
f =
3
volume of NH CNS
4
5.6 Calculation of r esults
The halide (excluding fluoride) content, expressed as the percentage by mass of chloride in the flux, is
given by Formula (3):
titret− itre ××0, 003 545 f
()
blanksample 3
× 100 (3)
05, d
which simplifies to:
0,709×V
f
3
d
where
is the volume, in ml, of ammonium thiocyanate solution (5.2.2) used in the titration of the blank,
V
minus the volume used in the titration of the flux sample;
d is the density, in g/ml, of the original flux sample, at 20 °C, determined by the use of a hydrometer;
f
is the correlation factor for the ammonium thiocyanate obtained in 5.5.
3
The halide content of the flux sample is given by the mean of the three results obtained on the triplicate
test samples.
As an alternative practice, the original 25 ml sample may be weighed and the final calculation adjusted
accordingly.
6 Method C: Titration method for the determination of halide (excluding
fluoride) content of water-soluble fluxes containing phosphates
6.1 Principle
Oxalic acid is added to complex any copper which is present in the flux and then ferric nitrate is added
to complex the phosphate. The halide content of the flux, calculated as chloride, is then determined
volumetrically using silver nitrate and ammonium thiocyanate. The method is not suitable for the
determination of fluoride.
5
© ISO 2022 – All rights reserved
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oSIST prEN ISO 9455-6:2022
ISO/FDIS 9455-6:2022(E)
This method is applicable to fluxes of class 331 as defined in ISO 9454-1.
6.2 Reagents
Only reagents of recognized analytical quality and distilled or deionized water with a conductivity less
than 10 μS/cm are to be used.
6.2.1 Silver nitrate solution (0,02 mol/l).
3,4 g of silver nitrate (AgNO ) is dissolved in water (see 4.2.2) then transferred to a 1-l volumetric flask
3
and diluted to the mark with water. This is mixed thoroughly. The silver nitrate (AgNO ) should be
3
dried at (110 ± 5) °C for 16 h and cooled in a desiccator before weighing.
Alternatively, a commercially available concentrate is used to prepare 0,02 mol/l standard silver nitrate
solution.
Standardize the silver nitrate solution using the method given in Annex A to derive the correlation
factor f . This is stored in an amber glass bottle.
1
NOTE 1 ml of silver nitrate solution is equivalent to 0,000 709 × f g of chloride ion.
1
6.2.2 Ammonium thiocyanate solution (approximately 0,02 mol/l).
1,6 g of ammonium thiocyanate (NH CNS) is dissolved in water then transferred to a 1-l volumetric
4
flask and diluted to the mark. This is mixed thoroughly. This solution is standardized with 0,02 mol/l
silver nitrate solution (6.2.1), as described in 6.5.
6.2.3 Nitric acid solution (10 % volume fraction).
100 ml of nitric acid (density 1,42 g/ml) are diluted to 1 l and mixed thoroughly.
6.2.4 Oxalic acid.
WARNING — Care should be exercised in the handling and disposal of this toxic reagent.
6.2.5 Ferric nitrate.
6.2.6 Nitrobenzene.
WARNING — Care should be exercised in the handling and disposal of this hazardous reagent.
6.
...
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