NATIONAL BUREAU OF STANDARDS REPORT

10 907

ELECTROLYTE DATA CENTER

Thermochemistry Section

Physical Chemistry Division

for

Office of Standard Reference Data

National Bureau of Standards

Washington, D.C.

U.S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
NATIONAL BUREAU OF STANDARDS

The National Bureau of Standards1 was established by an act of Congress March 3, 1901. The Bureau’s overall goal is to strengthen and advance the Nation’s science and

technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the Nation’s physical measure- ment system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau consists of the Institute for Basic Standards, the Institute for Materials Research, the Institute for Applied Technology, the Center for Computer Sciences and

Technology, and the Office for Information Programs.

THE INSTITUTE FOR BASIC STANDARDS provides the central basis within the United States of a complete and consistent system of physical measurement; coordinates

that system with measurement systems of other nations; and furnishes essential services leading to accurate and uniform physical measurements throughout the Nation’s scientific community, industry, and commerce. The Institute consists of a Center for Radiation Research, an Office of Measurement Services and the following divisions: Applied Mathematics—Electricity—Heat—Mechanics—Optical Physics

Linac

Radiation2—Nuclear Radiation 2—Applied Radiation2—Quantum Electronics3—

Electromagnetics3—Time and Frequency3—Laboratory Astrophysics3—Cryogenics3

. THE INSTITUTE FOR MATERIALS RESEARCH conducts materials research lead- ing to improved methods of measurement, standards, and data on the properties of

well-characterized materials needed by industry, commerce, educational institutions, and

Government; provides advisory and research services to other Government agencies;

and develops, produces, and distributes standard reference materials. The Institute consists of the Office of Standard Reference Materials and the following divisions: Analytical Chemistry—Polymers—Metallurgy—Inorganic Materials—Reactor Radiation—Physical Chemistry.

THE INSTITUTE FOR APPLIED TECHNOLOGY provides technical services to pro- mote the use of available technology and to facilitate technological innovation in industry and Government; cooperates with public and private organizations leading to the development of technological standards (including mandatory safety standards), codes and methods of test; and provides technical advice and services to Government agencies

upon request. The Institute also monitors NBS engineering standards activities and

provides liaison between NBS and national and international engineering standards

bodies. The Institute consists of a Center for Building Technology and the following

divisions and offices: Engineering Standards Services—Weights and Measures—Invention and Innovation—Product Evaluation Technology—Electronic Technology—Technical

Analysis—Measurement Engineering—Fire Technology—Housing Technology4 —Federal Building Technology4—Building Standards and Codes Services4—

Building Environment4—Structures, Materials and Life Safety4—Technical

Evaluation and Application4. THE CENTER FOR COMPUTER SCIENCES AND TECHNOLOGY conducts re- search and provides technical services designed to aid Government agencies in improving cost effectiveness in the conduct of their programs through the selection, acquisition,

and effective utilization of automatic data processing equipment; and serves as the principal focus within the executive branch for the development of Federal standards for automatic data processing equipment, techniques, and computer languages. The Center

consists of the following offices and divisions: Information Processing Standards—Computer Information—Computer Services —Systems Development—Information Processing Technology.

THE OFFICE FOR INFORMATION PROGRAMS promotes optimum dissemination and accessibility of scientific information generated within NBS and other agencies of

the Federal Government; promotes the development of the National Standard Reference Data System and a system of information analysis centers dealing with the broader

aspects of the National Measurement System; provides appropriate services to ensure

that the NBS staff has optimum accessibility to the scientific information of the world,

and directs the public information activities of the Bureau. The Office consists of the following organizational units: Office of Standard Reference Data-—Office of Technical Information and

Publications—Library—Office of International Relations.

1 Headquarters and Laboratories at Gaithersburg, Maryland, unless otherwise noted ; mailing address Washington, D.C. 20234.

2 Part of the Center for Radiation Research.

3 Located at Boulder, Colorado 80302.

* Part of the Center for Building Technology.
NATIONAL BUREAU OF STANDARDS REPORT

NBS PROJECT

316.0116 September 1, 1972

NBS REPORT

10 907

ELECTROLYTE DATA CENTER

Scope and Outline of Activities

Ralph L. Nuttall

Bert R. Staples

George T. Armstrong

Thermochemistry Section

Physical Chemistry Division

Institute for Materials Research

for

Office of Standard Reference Data

National Bureau of Standards

Washington, D.C. 20234

IMPORTANT NOTICE NATIONAL BUREAU OF STA

for use within the Government, f and review. For this reason, the whole or in part, is not authorii Bureau of Standards, Washingtor

the Report has been specifically p

i accounting documents intended Annroved for public release by the Ejected t0 additional valuation r . . n listing of this Report, either in Director of the National Institute ot

gfjj Ce 0 f Director, National Standards and Technology (NIST) the Government agency lor which on October 9, 201 5.

>ies for its own „s..

U.S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

Table of Contents

Page

Pre face

I Purpose * 3

II Scope 3

III Significance and Justification ...» 4

IV Organizational Affiliation ...... 6

V Resources *

VI Mode of Operation 11

VII Needs and Proposed Priorities 15

VIII Activities 19

IX Summary 24

Appendix 1 Scope of Properties , Substances, Ranges 25

Appendix 2 List of Publications Contained in Electrolyte

Data Center 28

Appendix 3 Sodium Chloride Monograph Prospectus ....... 34

Appendix 4 Scope of Current Literature 56

1

Preface

The Electrolyte Data Center was organized in-house

at the National Bureau of Standards in order to meet the needs of the

Technological and Scientific Community for reliable and carefully

evaluated data primarily in the field of aqueous electrolytes. An

informal steering committee consisting of Dr. Howard J. White,

Dr. David Garvin and Dr. George T. Armstrong made most of the preliminary

arrangements

.

In order to provide initial guidance to the Data Center in the

most fruitful and useful activities to be carried out, priorities to

be assigned, and other technical basis of activities, a Panel of the

National Academy of Sciences /National Academy of Engineering/Naticnal

Research Council was formed under the auspicies of Dr. Hendrick

van Olphen of the Numerical Data Advisory Board. This Panel consists

of Dr. Harold S. Friedman, Chairman; Dr. S. Bruckenstein

;

Dr. John T. Edsall, Dr. Alphonse Fortziati, Dr. George J. Janz

Dr. W. T. Lindsay; Dr. Ricardo Pytkowicz, and Dr. Robert E. Wood.

The Panel had its first meeting 27 October, 1971, in Washington,

D.C. at which a presentation was made of NBS activities related to the

Electrolyte Data Center and individual members of the Panel made

presentations. The meeting was summarized in a report dated

22 December 1971.

The present report, by the staff of the Electrolyte

Data Center, is at the same time a response to the December, 1971,

report of the Panel and a summary of Data Center activities up to the

present time.

George T. Armstrong, Chief

Thermochemistry Section

2

Electrolyte Data Center

I. Purpose. The purpose of the Data Center is to provide on a

continuing basis information services, evaluations, and

critical reviews of the the rmodynamic data on aqueous electrolytes.

II. Scope of Coverage. The data center will emphasize the study of

equilibrium thermodynamic properties of aqueous electrolyte

systems, and will cover the whole range of temperatures, pressures,

and concentrations for which data are available. A list of

physical properties falling within the scope of the data center's

primary concern is attached (appendix 1.). The data center will

take cognizance of certain related physical properties and also

of transport properties, but will not presume to provide complete

coverage of them. Solutions of single electrolytes in water will

be given primary emphasis. Mixed electrolyte solutions are

being studied by scientists at a rapidly increasing rate. These

solutions will be included in the activities of this data center.

Aqueous solutions of non-electrolytes and non-aqueous systems,

including fused salts, will not presently be covered by the data

center.

3
'
III. Significance and Justification.

A multitude of technological uses for electrolyte solution data

exist. Very important applications exist in the chemical process

industries and in the various electrochemical industries. Even a

very brief survey must also include areas such as environmental

protection, water resources management, physiological and biomedical

research, clinical practice and sanitation.

Industrial applications are widespread, and the fields of foods

and food processing, agriculture, textiles, refrigeration, and

construction must be included into the list of fields in which

applications are found.

As a simple illustration of a particular property, the osmotic

coefficient, in physiology, the following example can be cited.

The intercellular and extracellular fluids exist in a state of

osmotic equilibrium. This equilibrium is complex but does include

not only the colloidal osmotic pressure due to plasma proteins but

also the electrolyte osmotic pressure.

One of the most important characteristics of the internal cell

environment, which is critical to the normal life and activity of the

cell, is its total electrolytic osmotic pressure, and of all the

parameters of the extracellular fluid, this is the one that is most

strictly regulated. It may also be noted that the main constituent

in the extracellular water is sodium chloride.

4

The main protective mechanism of zinc rich paints is electrochemical. The fact that zinc metal is electropositive to iron and in

a simple aqueous galvanic cell will form the anode and react to

dissolve preferentially to the iron is of great importance for

protecting steel parts in a marine environment, for example, a ship

hull. Data on galvanic potentials are necessary for studies of corrosion

problems. Other examples of this type of sacrifical protection are

widespread in industry.

In many basic scientific methods for investigating thermodynamic

properties of aqueous solutions, for example, isopiestic measurement,

a few solutions, such as NaCl, serve as the reference standards. The

available data on such reference standards is critical to scientific

research in many areas. Other data often serve as the basis for

developing theories concerning the properties and behavior of electrolyte

solutions, which may result in important practical applications.

Reference data would also provide a means of testing theories and

models of electrolyte solutions.

In addition to the technological users of electrolyte data,

research scientists require sets of consistent and accurate data.

Theoretical studies of electrolyte solutions can be tested only by

use of such data. Chemists studying reactions in solution need data

on the properties of the species present in the solutions.

The need for electrolyte data within this enormous framework

indicates the usefulness of an Electrolyte Data Center to the scientific

and industrial complex.

5

IV Organizational Affiliation.

The Electrolyte Data Center is sponsored and initially funded by

the Office of Standard Reference Data (OSRD) (Dr. David R. Lide, Chief)

as part of the National Standard Reference Data System (NSRDS). In

the OSRD it is under the supervision of Dr. H. J, White, Jr., as part

of the program of Thermodynamics and Transport Data.

It is organizationally part of the Thermochemistry Section

(Dr. George T. Armstrong, Chief). The Thermochemistry Section is one

of five sections of the Physical Chemistry Division (Dr. M. D. Scheer,

Chief). The other sections are: Surface Chemistry (Dr. Ralph Kline,

Chief), Photochemistry (Dr. Pierre Ausloos, Chief), Radiation

Chemistry (Dr. Dolphius E. Mulligan, Chief), and Elementary Processes

(Dr. Henry M. Rosenstock, Chief). There are also in the Physical

Chemistry Division a Thermodynamics Group (Dr, C. W. Beckett, leader),

a Quantum Chemistry Group (Dr. Morris Krauss, leader), and a Data

Programs Group (Dr* David Garvin, leader).

In the Physical Chemistry Division Dr. David Garvin, as coordinator

of Data Programs, has general oversight of data centers in Kinetics,

Elementary Processes, and Chemical Thermodynamics, as well as the

Electrolyte Data Center. The Chemical Thermodynamic Data Center

(Mr. Donald D. Wagman, manager) is also in the Thermochemistry Section,

and interacts closely with the Electrolyte Data Center, but the two

Centers are physically and organizationally separate.

The Physical Chemistry Division is in the Institute for Materials

Research of the National Bureau of Standards (Dr. John D. Hoffman, Chief).

6
-1
V. Resources.

A. Personnel

The manager of the data center is Dr. Ralph L. Nut tall; the

principal other scientist is Dr. Bert R. Staples.

The initial funding of the data center permits operation at

a rate somewhat less than one man year per year. In the sixteen

months of operation to date, approximately one man year has been

funded. Of this time, Dr. Nuttall accounted for about 0.4 man year

and Dr. Staples has accounted for the remaining 0.6 man year for the

tasks of the Data Center. Dr. George T. Armstrong, Chief of the

Thermochemistry Section, provided administrative time as needed

Additional time, not reimbursed from project funds, was contributed

by several scientists associated with other programs. These included

Dr. Robert N. Goldberg, experimental thermochemistry; Mr. D. D. Wagman,

Dr. W. H. Evans, and Dr. V. B. Parker of the Chemical Thermodynamic

Data Center; Dr. David Garvin, Coordinator of Data Programs for the

Physical Chemistry Division; Dr. H. J. White, Office of Standard Reference

Data; Dr. W. J, Hamer NBS Electricity Division, now retired, and

Dr. Y. C. Wu, Institute of Applied Technology. Clerical assistance

was provided for a few months by Miss Cathy Worthington, a student

trainee. Miss Debra Miro of the Thermochemistry Section has handled

the bulk of the clerical operations for the Data Center since its

inception.

B. Space and equipment

The Data Center occupies Room A- 164 , Chemistry Building, a modified

2 laboratory- type module with about 23 m (3.2 m X 7.2 m) floor space.

3

It is equipped with six filing cabinets, about 40 book shelves (~2.8 m ),

7

and appropriate oLher office furniture.

Equipment assigned to the Data Center includes: Control

Data Corporation tape typewriter (Typetronic 2816) with tape reader

and tape punch; Friden electromechanical desk calculator; Wang 450

Scientific Calculator (electronic) with card program attachment (on

order); and a microcard reader. Also available in adjoining rooms

for use by the Data Center are Teletype typewriters with tape punch

and computer interface; IBM card keypunches, Hewlett Packard 7200A

Graphic plotter; 3M microfilm 400 Reader-Printer; and an Olivetti

Copia III quick copier.

General NBS equipment useful for the Electrolyte Data Center

includes the Univac 1108 computer, and special data and manuscript

processing facilities of the Office of Standard Reference Data.

C. Library and literature files

The ultimate library resource of the Electrolyte Data Center

is the NBS main library, which has one of the most complete

scientific collections in the nation. By interlibrary loan essentially

all the library resources of the nation are available for special

needs

Additional resources are provided by the library of the Office

of Standard Reference Data, which has a special collection of

evaluated scientific reference data, and the library and files of the

Chemical Thermodynamic Data Center. The applicability of the latter

to the needs of the Electrolyte Data Center is discussed below in more

detail.

8

In addition to the above, the Data Center has a special

collection of journals, books, and working files, emphasizing properties

of electrolytes. These are described below and in Appendix 2.

(1) Journals

The Data Center has the following journals in its files and

currently being received by subscription:

J. Phys. Chem.

J. Chem. Phys.

J. Chem. Soc. Faraday

J. Solution Chem.

J. Am. Chem. Soc.

Other journals received in the adjoining Chemical Thermodynamic

Data Center include:

Chemical Abstracts

J. Thermodynamics and Thermochemistry

J. Chem. Eng. Data

J. Research NBS

(2) Secondary Source Literature

The Data Center has on hand about 45 monographs and reference

works on thermodynamic and transport properties of aqueous and non-aqueous

electrolyte solutions. About ten additional books are on order. A

list of the books and other secondary source literature is given in

Appendix 2. Some other relevant monographs and reference works are

found in the Chemical Thermodynamic Data Center and are available to

the Electrolyte Data Center.

9

(3) Reports, reprints, and special files.

The technical files of the Electricity Division electrolyte data

project have been acquired. These consist of technical reports (listed

in Appendix 2), manuscripts in preparation, reprints, bibliographical

files, computer programs, partially evaluated data files.

Limited files of bibliographical material and some miscellaneous reports

on special topics discussed later in this report have also been obtained.

(4) Chemical Thermodynamic Data Center files.

The principal data files for use of the Data Center are those

of the Chemical Thermodynamic Data Center. The relationship of

these files to the work of the Electrolyte Data Center is discussed

in Section VI. These files comprise, perhaps, the largest indexed files

related to chemical thermodynamic properties existing in the world.

The files of the Chemical Thermodynamic Data Center may be outlined

briefly as follows.

(a) Substance-property index card file (more than 100,000 items).

These files are classified by substance, including organic and inorganic

substances. Recent accessions (about three years) are completely stored

on magnetic tape so that storage, retrieval, and sorting manipulations

are possible. Each substance is indexed in ten categories of thermo

dynamic properties. Each card gives bibliographical information about

the single source of the data described on it.

(b) Reprint file (microfilm). Complete articles are stored on

microfilm, and filed with complete bibliographical information

in alphabetical order of first author's surname.

(c) The Bulletin of Thermodynamics and Thermochemistry is prepared

by the Chemical Thermodynamic Data Center and the information contained

is on magnetic tape with taachine-search capabilities available.

10

VI Mode of Operation of the Data Center.

The Electrolyte Data Center has the following functions:

(1) Acquisition and organization of information on the properties

of electrolyte solutions (coordinated with the work of other

data centers).

(2) Provision of information services on electrolytes directly

to the public and the scientific community.

(3) Preparation and dissemination of lists , bibliographies,

surveys, and critical reviews relating to the field of

electrolyte solutions.

These are discussed briefly below.

(1) The acquisition of information from the primary source

literature (mainly technical journals) consists first of a search in

which relevant articles are identified and obtained. This is then

followed by an abstracting process in which the relevant information

and data are abstracted from the article and stored in a retrievable

mode. This information may then be organized by substance, by property

by source, and in other ways for ready retrieval. To do a complete

search such as this is a very large task.

The Data Center is not conceived as a completely self-sufficient

operation, but will depend upon other data compilation activities for

at least part of its technical files. In this instance, the work

of the center will be coordinated with that of the Chemical Thermodynamic

Data Center.

In the Chemical Thermodynamic Data Center a very thorough search

of the current chemical literature is made on a continuing basis.

11

This search includes scanning the contents of about forty-five important

journals in which is found a large fraction of the significant work

in thermochemistry and thermodynamics. It also includes scanning page

by page most sections of the Chemical Abstracts. Following this search,

the articles and abstracts are examined closely for thermodynamic

information, and those which contain such information are accessed

for the files of the Chemical Thermodynamic Data Center. This accession

includes preparation of a bibliographical reference and preparation

of a microfilm copy of the article for the files.

In the Electrolyte Data Center this search will not be duplicated.

The subject and substance coverage of the search initially performed

by the Chemical Thermodynamic Data Center included most, of the subjects

required for the Electrolyte Data Center. By a minor expansion of the search

complete coverage of the topics listed for emphasis in Appendix 1 is being

obtained. Subjects for which prior coverage was inadequate, but which

are now being covered as completely as other topics are: density,

expansibility, compressibility, phase diagrams (aqueous), solubility,

salting coefficients, and changes of freezing and boiling points. Transport properties, surface tension, dielectric constant, and other

properties not emphasized in Appendix 1 are not included among the

subjects for which articles are accessed.

As a result of this, the files of the Chemical Thermodynamic

Data Center will, for current and future primary source literature

be nearly complete with respect to all properties emphasized in

Appendix 1. References to prior work will be notably deficient in the

12

newly covered topics mentioned above. These deficiencies will be

dealt with as required in particular applications of the work of the

Center.

A second phase of the accession of information for the Chemical

Thermodynamic Data Center files is the abstraction of data from the

articles in the files. This provides the principal information for

the subject-property files. This is a process for which the work can

be divided so that articles containing data relevant to the Electrolyte

Data Center can be abstracted in the Electrolyte Data Center supplementing

the work of the Chemical Thermodynamic Data Center. The information

thus obtained will be merged with the Chemical Thermodynamic Data

Center files. Copies of the abstracted information may also be kept

in the Electrolyte Data Center

(2) Close contact will be maintained by correspondence and

personal contacts with selected scientists in the field, and with

organizations having special interest in the field of electrolytes

and solution processes.

This type of contact is important (1) to maintain awareness in the

Data Center of work in progress elsewhere, (2) to determine the impact

of scientific data for electrolytes on technological programs, (3) to

establish and maintain liaison between the Data Center and potential

users

(3) The principal productive activity of the Data Center is to

prepare material for distribution. The material may be prepared in

response to requests for information or may be prepared in response

to anticipated needs. Three categories of output material ma)' be

identified and are given below.

13

(1) Lists and Bibliographies

(2) Surveys (no evaluation of data)

(3) Critical Reviews (critical evaluation of data)

Examples and priorities are given in Section VII.

14

VII Needs and Proposed Priorities.

Three categories of outputs identified in Section VI are discussed

here with respect to particular examples. Examples are listed in

each category in order of their priorities assigned on the basis of

need, cost, difficulty of completion, and availability of personnel.

1. Lists and Bibliographies

(a) List of laboratories active in the field

(b) List of data centers active in the field

(c) List of scientists active in the field

(d) Bibliography of reference works in electrolyte thermodynamics

(e) Bibliographies of primary source literature in special

areas of electrolytes

(f) Annual bibliography of work done and cumulative bibliography

2. Surveys (no evaluation of data)

(a) Subject-property index of previously compiled data

(reference literature) on electrolytes

(b) Subject-property index of annual work done and cumulative index

(c) Uncritical compilations of data in selected areas

(d) Surveys of schemes for estimating particular properties

3. Critical Reviews (critical evaluation of data)

(a) Thermodynamic properties of aqueous uni-polyvalent

electrolytes and poly- polyvalent electrolytes

(1) Osmotic coefficients and activity coefficients at 25°C

(2) Thermal properties

(b) Single-substance monographs with broad coverage of selected

substances (NaCl), (CO^, HCO^ , CO^ )

15

(c) Thermodynamic properties of biological electrolytes

(d) Monograph on selected properties of about 100 key electrolytes

I (e) Critical evaluation of material in the Sillen- Martel compendia

Of the lists and bibliographies a single compilation combining

items (a), (b), and (c) can be prepared in a relatively short time.

It is given a high priority because of its ease of preparation, its

brevity, and its general utility to scientists and technologists

interested in electrolyte properties. A bibliography of reference

works (d) in electrolyte thermodynamics is also easy to prepare but

has less general utility. Bibliographies of primary source literature

(e), in special areas and annual and cumulative bibliographies are good

awareness information; however they tend to be outweighed in importance

by subject-property indexes.

The proposed surveys of electrolyte thermodynamic data are based

on our own conviction that there is no better way to become thoroughly

aware of the work being done in the field than to prepare such

surveys; and that the information thus gained would be of greater

value if disseminated than if retained in our own files. In particular,

a survey of previously compiled work found in the reference or

secondary source literature provides a guide to the kind and currency

of information already published. It thus provides important information

needed in assigning priorities for extensive critical reviews. Thus

its greatest value will probably be in the operation of the Electrolyte

Data Center. It will indicate what types of data, and on what substances

these data are available in the well-known and some of the lesser known

16

secondary sources and monographs on electrolytes.

An annual and cumulative index classified by subject and property

with associated bibliography essentially consists of a fraction of

the work already appearing in the annual Bulletin of Thermochemistry

and Thermodynamics, augmented with respect to certain properties. A

separate listing of the electrolyte information would probably be more

intensively read in a narrower circle of readers. However, the priority

is somewhat reduced by the existence of the Bulletin as an alternate

source of the same information.

Under critical reviews (3) priorities are difficult to assign.

First priority is given to completing osmotic coefficients and

activity coefficients of the electrolytes in addition to uni -univalent

charge types. This work was begun by Wu and Hamer. The completion

requires up-dating available data from 1967 where Wu and Hamer

stopped compilation. However, the extensive work already done should

not be lost and its existence reduces the effort needed to complete

the publication of this monograph.

A single-substance monograph on NaCl (b) was proposed by

Dr. W. T. Lindsay, based on the ubiquity of NaCl in the physical

and biological sciences and in industrial processes. The suggestion

was favorably viewed by the study group. This monograph, containing

critically evaluated data, will be a comprehensive review of the system

NaCl-^O. The reviews will cover all available thermodynamic

properties and related information over all ranges of pressure,

temperature, and concentration. An outline of such a monograph is

given in Appendix 3.

17

Thermodynamic properties of biological electrolytes (c) are

very important new and a review would be particularly useful for an

international subcorranission associated with the IUB-IUPAB- IUPAC , The

principal difficulty is lack of a suitable staff person. When a

person to do this work is available, it assumes a high priority.

A monograph on selected properties of some carefully selected

key electrolytes (d) would be very useful. These compounds can serve

as reference standards and as models for the properties of other

substances where no experimental data are available.

18

VIII Activities of the Data Center.

This section covers the principal activities carried on in and

in behalf of the Data Center since its inception.

1. Organization and physical establishment of the Data Center

The center was brought into being by a steering committee

(White, Garvin, Armstrong), staffed (see Section III), provided

with space and some physical facilities (see Section IV),

and arrangements were made for an advisory panel of the

Numerical Data Advisory Board (NAS-NAE-NRC)

2. Establishment of program and priorities

(a) The ad-hoc panel on thermodynamic properties of aqueous

electrolyte solutions (H. L. Friedman, Chairman) met

27 October 1971, at the National Academy of Sciences,

with Data Center staff and other interested scientists

in attendance. The report of this panel, submitted

22 December 1971, was carefully analyzed and strongly

influenced the present document, which is in part a

response to the report.

(b) An in-house study group met weekly or bi-weekly during

a period of several months to help establish guidelines

for the activities of the Data Center. The composition

of this study group varied somewhat, but included:

Dr. G. T. Armstrong, Dr. R. L. Nuttall, Dr. B. R. Staples,

of the Data Center staff. Dr. R. N. Goldberg of the

Thermochemistry Section; Mr. D. D. Wagman, Dr. W. H. Evans

19

and Dr. V. B. Parker of the Chemical Thermodynamic

Data Center; Dr. W, J. Hamer of the Electricity

Division; Dr. Ii. J. White, OSRD; and Dr. D. Garvin,

Physical Chemistry Division office.

The study group was convened to carry out technical discussions

that would allow definition of the scope and extent of electrolyte data

evaluation and procedures for the operation of the Data Center. The

study group considered and discussed in detail the following subjects:

(1) The extent and types of existing compilations and current

literature on electrolyte properties.

(2) Extent of coverage of appropriate properties by the Chemical

Thermodynamic Data Center, and modes of interaction between

the two Centers

(3) Relationships between technical treatments of electrolyte

data by Hamer and Wu and by the Chemical Thermodynamic Data

Ce nter

(4) A compendium of subject-property information in the secondary

source literature (existing reference works).

(5) Selected monograph subjects (see Section VII for topics and

priorities

As a result of these discussions the scope of the Data Center was

limited to aqueous solutions and to thermodynamic properties. It does

not appear feasible to include non-aqueous solutions or transport

properties in the data center operations at this time. It was also

agreed that the Electrolyte Data Center should take advantage of the

existing files and abstracting procedures already in operation in the

20

Chemical Thermodynamic Data Center. Duplication of effort is to

be avoided.

Discussions were held with Mr. Wagman to review the operations of

this data center and to establish a system for obtaining abstracts of

articles dealing with electrolyte solutions.

3. Completed work

(a) The monograph on activity and osmotic coefficients for

uni-univalent electrolytes at 25°C by W. J. Hamer and

Y. C. Wu was reviewed in detail and the tables and

constants were verified using the computer programs

developed by Hamer and Wu. Corrections and some modifications

were recommended. This monograph is now in press in the

Journal of Physical and Chemical Reference Data (Issue No. 4.).

(b) A substantial amount of the data that had been acquired

from Hamer on computer cards has been placed on magnetic

tape to allow more efficient use of storage space in the

Data Center. Two tapes will be used; one to be retained

on file by the NBS Computer Services Division and one to

be stored in the Data Center. The computer cards will

be stored in inactive storage space at the NBS records

storage area. At least once a year the magnetic tape will

be recopied onto a new tape to preserve the quality of

the tapes over long storage periods.

(c) The machine programs developed by Hamer and Wu to correlate

activity coefficients and osmotic coefficients are

21

generally applicable to electrolytes of various valence

types. They provide theoretical fits in the Debye-Hackel

region and empirical polynomial fits in the more concentrated solutions. They are complete and are considered

to be of sufficiently general interest for the Data

Center to make them available as NBS Reports or Technical

Notes

Technical Work in Progress

(a) A compendium of information available in data compilations

and secondary source literature (reference works) on

properties of aqueous electrolytes has been started and

is in preparation,

(b) A study was made of the extent of technical literature

to be covered by the Electrolyte Data Center. This study

in intended to provide guidance as to the amount of personnel

effort needed to cope with organization of the data and

files and to review and evaluate the data. The study is

summarized in Appendix 4.

(c) A partial bibliography of data sources, both primary and

secondary sources, for numerous properties of NaCl has

been prepared. This was initiated in preparation for a

monograph on aqueous sodium chloride. The monograph was

outlined (see appendix 3)

(d) A compilation of most of the primary reference sources

for osmotic and activity coefficient data at 25°C has

been completed for 1:2, 2:1, 1:3 and 3:1 electrolytes up

to about 1968. The critical evaluation of the data was

initiated by Hamer and Wu.

22

(«0 A list of workers in the field of electrolytes was begun.

(f) Initial steps have been taken to establish corranunicat ions

and cooperative relationships with other data centers in

the field. The symposium in honor of H. S. Frank (Pittsburgh

June, 1972) was attended. Letters to persons active in

electrolyte solution research are being prepared, not only

to allow the Center to keep abreast of recent developments

but also to maintain a helpful liaison with regard to

their opinions of the usefulness of various projects that

the Electrolyte Data Center may undertake. Letters to

other data centers outside of NBS will not only inform

them of our operations but will also provide interaction

through requests for information and services and sharing

of some reference data.

23

IX Summary.

This document has presented the scope and activities of the

Electrolyte Data Center. These are limited by funds and personnel

available. Dependence on the Chemical Thermodynamic Data Center

for literature searching has been pointed out. In section VII are

given some possible activities, with some estimates of priorities,

of the data center. In section VIII the present activities are discussed.

Activity will be transferred to other tasks as present ones are

completed.

The data center will try to respond to all needs expressed

by the scientific community within the scope of its activities.

24

Appendix 1„

Properties

I. Scope of properties

A. Treatment of properties in the following modes will be of

interest.

1.

a. Experimental treatments

b. Theoretical treatments

2.

a. Molar quantities

b. Specific quantities

3.

a. Partial quantities

b. Apparent quantities

4. T^PjX variables

B. The functions that describe these properties are also readily

classified into four types.

1. Energy functions of aqueous solutions

a. Internal energy (U) (dU/BT)V (5U/dV)T

b. Enthalpy (H) (3H/BT)P (SH/dP)T

c. parameters associated with phase changes (AH and

fus

; also freezing point lowering and boiling point

elevation) .

2.

Ordering functions of aqueous solutions

a

Entropy (S)

3.

Equilibrium functions

a

Helmholtz energy (A)

b. Gibbs Energy (G)

c

E.M.F. and chemical potentials (E, p)

25

d. Equilibrium constants and related T and P.

K , K, . K . , K, . K , K. (assoc), P , solubility,

a’ b' V instab sp* A

’ vap’

phase diagram and associated activity coefficients

(osmotic coefficient; mean activity coefficients)

4. PVT relationships

a. density of aqueous solutions and associated molar

vo lume

b. expansibility

c. compressibility

C. The remaining related physical properties which are not to be

emphasized at this time, fall into two categories:

1. Transport properties

a. conductivity-electrical

b. conductivity- thermal

c. diffusion

Including related constants such as:

(a) diffusion coefficient

(b) transference number

(c) ionic mobility

(d) viscosity

2. Related physical properties

a. dielectric constant

b. light absorption coefficients

c. polarization

d. surface tension

e. ionic radius

26

f. decomposition potential

g. velocity of sound in solutions

h. electro-kinetic properties (e.g. voltammetry--polarography, etc.)

II. Classes of substances and systems

Systems in both aqueous media and mixed solvents that include water

as one component

a. Strong electrolytes

b. Weak electrolytes

c. Mixed electrolytes

d. Zero -charge types of solutes

III. Ranges of Properties

A. Temperature -- From -30 to +400°C is needed with special

interest in the range from 0 to 40°C, and in particular 25°C.

B. Pressure -- From 0-1000 atmospheres is needed (10,000 atm,

as an upper limit), with special interest at 1 atmosphere.

C. Concentration -- From infinitely dilute solutions (X = 0) to

saturation, with special emphasis on standard states.

27

Appendix 2.

List of Publications Contained in the Electrolyte Data Center

Books

Bates, R. G. , Determination of pH, John Wiley and Sons, New York,

second edition, 1965.

Chariot, G. , Collumeau, A., and Marchon, J. C., Selected Constants:

Oxidation-Reduction Potentials of Inorganic Substances in

Aqueous Solution, Butfcerworths, London, 1971

Christensen, J. J, , and Izatt, R. M. , Handbook of Metal Ligand

Heats and Related Thermodynamic Quantities, Marcel Dekker, Inc.,

New York, 1970.

Coetzee, J. F., and Ritchie, C. D., eds„, Solute-Solvent Interactions,

Marcel Dekker, New York, 1969.

Conway, B. E,, Electrochemical Data, New York: Elsevier Publishing

Company, 1952.

Durst, R. A., ed., Ion-Selective Electrodes, NBS Spec. Pub. 314,

available from U.S. Government Printing Office, Washington, D.C. 20402, 1969.

Harned, H. S., Q^en, B. B., The Physical Chemistry of Electrolytic

Solutions, New York, Reinhold Publishing Corporation, third

edition, 1958.

Hirschfelder , J. 0., Curtiss, C. F., and Bird, R. B., Molecular

Theory of Gases and Liquids, John Wiley and Sons, New York,

second printing, 1964.

Horne, R. A., ed., Water and Aqueous Solutions —Structure, Thermodynamics, and Transport Properties, Wi ley-Interscience , Div.

of John Wiley and Sons, Inc., New York, 1972.

Kavanau, J. L. , Water and Solute-Water Interactions, Holden Day, Inc.,

San Francisco, 1964.

Keenan, J. H. , et al. Steam Tables, Thermodynamic Properties of Wate

Including Vapor, Liquid, and Solid Phases (Metric Units),

New York, John Wiley and Sons, Inc., 1966.

28

Kirillin, V. A., ed., (Kazavchinski, Ya. Z., et al), Heavy Water--

Thermophys ica 1 Properties, Moscow-Leningrad 1963, available from

U.S. Dept, of Commerce, National Tech. Information Service

(TT 70-50094), Springfield, VA 22151, 1971.

Kortum, G., Vogel, W. , and Andrussow, K. , Dissociation Constants

of Organic Acids in Aqueous Solution, Butterworths, London,

1961.

Krestov, G. A. , Chairman, Transactions of the All Union Symposium

on Thermochemistry of Electrolyte and Non-Electrolyte Solutions

(in Russian), Ivanovo, 1971.

Latimer, W. M. , The Gxidation States of the Elements and the

Potentials in Aqueous Solution, second edition, Englewood

Cliffs, New Jersey: Prentice-Hall, Inc., 1959.

Linke, W. F. , Solubilities: Inorganic and Metal-Organic Compounds--

A Compilation of Solubility Data from the Periodical Literature

Volume I: A-Xr, Volume II: K-Z, fourth edition, Princeton,

New Jersey: D, Van Nostrand Company, Inc., Volume I; Washington

D.C., 1958: American Chemical Society, Volume II, 1965.

Mancy, K. H. , Instrumental Analysis for Water Pollution Control,

Ann Arbor Science Publishers, Inc., Ann Arbor, Michigan, 1971.

Mishchenko, K. P. and Poltoratskiy, G. M. , Some Aspects of the

Thermodynamics and the Structure of Aqueous and Non-Aqueous

Electrolyte Solutions (in Russian), "KHIMIYA" Publishing

House, Leningrad, 1968.

Office of Critical Tables, National Academy of Sciences-National

Research Council Publication 976, Consolidated Index of

Selected Property Values (Physical Chemistry and Thermodynamics)

Washington, D.C., 1962.

Perrin, D. D., Dissociation Constants of Inorganic Acids and Bases

In Aqueous Solution, Butterworths, London, 1969.

Perrin, D. D., Dissociation Constants of Organic Bases in Aqueous

Solution, Butterworths, London, 1965.

Petrucci, S., ed., Ionic Interactions, Vol. I. Equilibrium and Mass

Transport, Vol. II. Kinetics and Structure, Academic Press,

New York, 1971.

Pitzer, K. S., and Brewer, L. , Lewis and Randall's Thermodynamics,

second edition, McGraw-Hill Book Company, Inc., New York,

New York, 1961.

Robinson, R. A., Stokes, R. H. , Electrolyte Solutions, The Measurement

and Interpretation of Conductance, Chemical Potential and

Diffusion in Solutions of Simple Electrolytes, second edition (revised),

London, Butterworths, 1965.

29

Samoilov, 0. Ya . , Structure of Aqueous Electrolyte Solutions and the

Hydration of Ions, Consultants Bureau, New York, 1965 (third

printing, 1969).

Sillen, L. G. , Martell, A. E. (compilers). Stability Constants of

Metal Ion Complexes, Section I: Inorganic Ligands, Section II:

Organic Ligands, second edition. Special Publication No. 17,

The Chemical Society, London, England, 1964 and Supple. 1,

Special Publication No. 25, 1971.

Washburn, E. W, , Editor-in-chief, International Critical Tables,

Volumes I through VII, McGraw-Hill, New York, 1926-1930.

Weissberger and Rossiter, Eds., Physical Methods of Chemistry, Vol. I. Techniques of Chemistry’-, Parts IIA 4- B Electrochemical Methods:

Wiley- Interscience, New York, 1971.

30

Reports and Pamphlets:

Barduhn, A. J., et al, Further Properties of Hydrates and Hydrating

Agents; Office of Saline Water, R and D Report No. 88 , 1964.

Barbuhn, A. J. , et al. The Properties of Gas Hydrates and Their

Use in Demineralizing Sea Water; Office of Saline Water,

R and D Report No. 44, 1960.

Caton, G. M. , et al, Mercury in the Environment--an Annotated

Bibliography, Oak Rdige National Laboratory Report GRNLEIS-71-8, Oak Rdige, Tennessee, 1972.

Fabuss, B. M. , et al. Thermodynamic Properties of Saline Water;

Office of Saline Water, R and D Report No. 136, 1965.

Fabuss, B. M. , et al. Thermophysical Properties of Saline Water

Systems; Office of Saline Water, R and D Report No. 189, 1966.

Kose, K. A., ed.. Bibliography on Structure of Clathrate Hydrates and

Related Topics; Office of Saline Water, R and D Report No. 121,

1965.

Page, C. H. and Vigoureux, P., The International System of Units

(SI); NBS Special Publication 330, 1971.

Office of Saline Water, Saline Water Conversion Reports for

1965, 1966, 1968, U.S. Dept, of Interior.

Butler, J. N. , The Use of Amalgam Electrodes to Measure Activity

Coefficients of Metal Salts in Multicomponent Salt Solutions--

Interim Report June 1, 1965-July 31, 1968, for Office of

Saline Water by Tyco Laboratories.

Reynolds, A. F., Properties of Electrolytes in Mixed Solvents.

I. Viscosity of Electrolytes in Dioxane-Wa ter, II. Conductance

of Alkali Halides in Dioxane-Wa ter Mixtures. University

Microfilms, Inc., Ann Arbor, Michigan, 1966.

Than, M. , A study of the Conductivity in Pure and Mixed Solvents

and at Various Temperatures of Electrolytes from Dilute to

Saturated Concentrations A. MgC^ in H2 O-C2 H5 OH, B. CsCl in

H

2 O-G

2 H

5 OH, University Microfilms, Ann Arbor, Michigan, 1968.

31

Swarts, E. L. , The Conductance of Dilute, Aqueous Solutions of

Electrolytes at 25 °C, University Microfilms, Ann Arbor, Michigan

1954. '

Vaughan, W. E., Tables of Dielectric Constants, Dipole Moments, and

Dielectric Relaxation Times, From Digest of Literature on Dielectrics 33, 21 (1969), National Academy of Sc iences

32
.
NBS Reports:

NSRDS-NBS 1. National Standard Reference Data System- Plan of

Operation, Brady, E. L. and Wallenstein, M. D., 1964.

NSRDS-NBS 2, Thermal Properties of Aqueous Uni-univalent Electrolytes,

Parker, V. B., 1965.

NSRDS-NBS 8 Part 1 NSRDS-NBS 16 Part 2, Thermal Conductivity of Selected Materials,

Part 1 and 2, Power, R. W. , Ho, C. Y. , and Liley, P, E.;

Part 1 - 1966, Part 2, 1968.

NSRDS-NBS 15 Volume 1 NSRDS-NBS 28 Volume 2, Molten Salts, Vol. 1, Electrical Conductance,

Density, and Viscosity Data, Janz, G. J., et al; Molten Salts,

Vol. 2, 1. Electrochemistry, 2. Surface Tension Data, Janz, G. j.

et al, 1969.

NSRDS-NBS 24, Hamer, W. J. , Theoretical Mean Activity Coefficients

of Strong Electrolytes in Aqueous Solutions From 0 to 100°C,

National Bureau of Standards, Washington, D.C., 1968.

NSRDS-NBS 33, Electrolytic Conductance and the Conductances of the

Halogen Acids in Water, Hamer, W. J. and DeWare, H. J. , 1970.

NBS Tech. Note 470, Messina, C. G. and Hilsenrath, J. , Edpac:

Utility Program for Computer-Assisted Editing, Copy-Production,

and Data Retrieval, 1969.

NBS Tech. Note 500, Messina, C. G. and Hilsenrath, J. , Edit-Insertion

Programs for Automatic Typesetting of Computer Printout, 1970.

NBS Tech. Note 553, Lide, D. R. , Critical Evaluation of Data in the

Physical Sciences--a Status Report on NSRDS, 1970.

NBS Tech. Note 554, Weisman, H. M. and Sherwood, G. B. , Annotated

Accession List of Data Compilations of the NBS Office of

Standard Reference Data, 1970.

NBS Tech. Note 270-3, Selected Values of Chemical Thermodynamic

Properties (first 34 elements), Wagman, et al, 1968; 270-4

(elements 35-53), Wagman, et al, 1969; 270-5 (elements 54-61)

Wagman, et al, 1971; 270-6 (elements 92-97), Parker, et al,

1971.

NBS Tech. Note 290, Alt, F. L. , Information Handling in the National

Standard Reference Data System, 1966 (reprinted 1967).

NBS Monograph 84, Hamer, W. J. , Standard Cells, Their Construction,

Maintenance, and Characteristics, National Bureau of Standards,

January 15, 1965.

33

Hamer, W . J . NBS

Report

9040

9047

9394

9432

9472

9573

9812

9876

9908

9979

10052

10076

10088

, et al, Electrochemical Data, Series of NBS Reports.

Part

I (Terms) 1966

II (The ore t . Eqn) 1966

III (Conductance) 1966

IV (Conductance HCi) 1966

V (Conductance halogen acids) 1967

VI Electrochemical Studies in Non-Aqueous

Solvents, Gedansky, L. M. and Pribaldi

K. S,, I. Acetonitrile.

VII Electrolytic Conductivity of Aqueous

Solutions of Hydrobromic Acid, 1967

VIII Hepler, L. G. , Oxidation Potentials for

Some Transition Elements, 1967

IX Electrolytic Conductivity of Aqueous

Solutions of Hydrofluoric Acid, 1968

X Electrolytic Conductivity of Aqueous

Solutions of the Alkali Metal Hydroxides, 1968

XI Osmotic Mean Activity Coefficients of

Aqueous Solutions of HC1, HBr, HI, and the

Chlorides, Bromides and Iodides of the

Alkali Metals at 25°C, 1968, (Wu and Hamer)

XII Electrolytic Conductivity of Aqueous Solutions

of the Sodium Halides, 1969

XIV Osmotic Coefficients and Mean Activity Coefficients

of a Series of Uni-Bivalent and Bi-Univalent

Electrolytes in Aqueous Solutions at 25°C, 1969

XV Electrolytic Conductivity of Aqueous Solutions

of the Potassium Halides, 1969

XVI Osmotic Coefficients and Mean Activity Coefficients

of a Number of Uni-Trivalent and Tri -Univalent

Electrolytes in Aqueous Solution at 25°C.

33a

Appendix 3.

Sodium Chloride Monograph Prospectus

Note: The prospectus on aqueous sodium chloride is a

preliminary arrangement of possible data which may be included in

such a monograph. The tables and values given are used only as

illustrative examples of possible forms that the data presentation

may take. It is not intended as a complete outline.

34

Aqueous Sodium Chloride

1. Introduction

A. Purpose of the monograph

Over the years a copious amount of data of both valuable

as well as less valuable results , has been compiled on the properties

of the system: Sodium chloride-Water . Various investigators have

reported careful studies on limited regions of temperature , pressure,

and concentration. At times, evaluations of such data for various

selected properties covering segments of the available data have

appeared. Yet, to our knowledge, no comprehensive treatment and

critical evaluation of all the available thermodynamic data has been

published

It, therefore, appears timely that an exhaustive collection

of data and its critical evaluation be made to represent accurately

the behavior of the sodium chloride-water system within the wide

ranges of temperature, pressure, and concentration in which data are

available.

This evaluation will not only update previous treatments of

data but also will bring together a comprehensive collection of

data in one critical review.

35

B. Summary of secondary data sources

A list of general sources of data compilations:

1. Bulletins of Thermodynamics and Thermochemistry

2. Chapman and Newman, A Compilation of Selected Thermodynamic

and Transport Properties of Binary Electrolytes in Aqueous

Solution, (1968)

3. Circular 500 Series

4. Harried and Owen, The Physical Chemistry of Electrolyte

Solutions, (1958)

5. International Critical Tables

6. JANAF Tables

7. Kaufmann, D. W. , Sodium Chloride (1960)

8. Lewis and Randall, Thermodynamics, (1961)

9. Office of Saline Water Reports

10. Parker, Thermal Properties of Aqueous Uni-univalent

Electrolytes

11. Robinson and Stokes, Electrolyte Solutions, (1965)

12. Wu and Hamer, (Osmotic and Activity Coef ficients . . .at 25°C) , (1968)

36

2.

Thermodynamic properties

a. Standard state of hypothetical lm aqueous solution

at T = 298.15 kelvins (25°G) (Ref. 1)

1. Heat of formation

AH° = -97.302

2. Free Energy of formation

Z£° = -93.939

3. Equilibrium constant of formation

log^R^. = 68.8560

4. Entropy in solution

£>298 = 27.6 cal deg "mol

L

[Na* + Cl" = 14.4 + 13.17 = 27.57]

37

b. Heat Capacity

V. Parker (2) has evaluated heat capacity as a function of

temperature and this is illustrated in Table 1.

Table <S0fc. Heat capacity: aqueous NaCl

n m 15

° 20° 25° 30°

00 0.90 - 25.2 - 23.3 - 21.5 — 20.

100,000 .000555 - 25.1 - 23.2 - 21.4 - 20.0 50,000 .00111 - 25.0 - 23.1 - 21.3 - 19.9

20,000 .00278 1 - 24.9 - 23.0 - 21.2 - 19.8 10,000 .00555 — 24.8 - 22.9 - 21.1 - 19.6 7,000 .00793 - 24.7 - 22.8 - 21.0 - 19.5 5,000 .oilio - 24.6 - 22.7 - 20.9 - 19.4 4,000 .01388 - 24.5 - 22.6 - 20.8 - 19.3

3,000 .01850 - 24.4 - 22.5 - 20.7 - 19.2 2,000 .02775 - 24.2 - 22.3 - 20.4 - 19.0 1,500 .03700 - 23.9 - 22.0 - 20.2 - 18.8 1,000 .05551 - 23.4 - 21.6 - 19.8 - 18.4 900 .0617 - 23.3 - 21.4 - 19.6 - 18.2

800 .0694 - 23.1 - 21.3 - 19.5 - 18.1 700 .0793 - 22.8 - 21.0 - 19.3 - 17.9 600 .0925 - 22.5 - 20.8 - 19.0 - 17.6 500 .1110 - 22.0 - 20.3 - 18.6 - 17.3 400 .1388 - 21.4 - 19.8 - 18.2 - 16.9

300 .1850 - 20.5 - 19.0 - 17.5 - 16.2 200 .2775 - 19.0 - 17.5 - 16.3 - 15.1 150 .3700 - 17.7 - 16.4 - 15.2 - 14.1 100 .5551 - 15.5 - 14.8 - 13.4 - 12.5 75 .7401 - 13.6 - 12.6 - 11.7 - 10.9

50 1.1101 - 10.4 - 9.6 - 8.8 - 8.2 40 1 3877 - 8.3 — 7.6 - 7.0 — 6.4 30 1.8502 - 5.7 - 5.1 - 4.6 - 4.1 25 2.2202 - 3.5 - 2.9 - 2.4 - 2.0 20 2.7753 - 0.8 - 0.4 0.0 + 0.2

15 7ftft.l + 3.3 3.5

19 6.3

in 9.0 Q ^

i)t dJv/O 9.7 Q ft 10.5

38

c Relative Apparent Molal Enthalpy has been similarly evaluated

(Ref. 2) and is presented in Table 2.

Table §1 Thermal properties of aqueous NaCl at 25 "C

n m <tv l\

00 0.00 472

callmole

0 callmole 0

100,000 .000555 436 11 16 50,000 .00111 423 14 21 20,000 .00278 395 22 32

10,000 .00555 365 31 45

7,000 .00793 344 37 52

5,000 .OHIO 322 42 59

4,000 .01388 304 46 6-4 3,000 .01850 282 51 70

2,000 .02775 245 59 79

1,000 .05551 167 73 93

900 .0617 155 75 94

800 .0694 139 78 96

700 .0793 120 80 97 600 .0925 99 83 98 500 .1110 71 85 97

400 .1388 + 35 87 94

300 .1850 -14 88 85

200 .2775 -87 83 + 60

100 .5551 -220 49 -33

75 .7401 -275 + 20 -98

50 1.1101 -344 -41 -222

40 1.3877 -373 — 85 -304

30 1.8502 -394 -156 -424

25 2.2202 -394 -207 -501

20 2.7753 -376 -274 -587

15 3.7004 -321 -367 -676

12 4.6255 -242 -430 -6<K)

10 5.5506 -135 -469 -628

9.5 5.8427 -93 -476 -588

39

d Heat of neutralization has been determined in various laboratories

and Table 3 (Ref. 2) shows the results of each.

3

Table WBt. AH° at 25 °C

n, moles HjO/mole solute Original

Investigator System Hemp of No. of ~ AHh,(T) -AW.v, -a//;. meas meas (25 °C) <25 °C) Acid Base Salt

°c callmole cal!mole callmole Richards and Rowe [224J NaCi 100 100 201 16.80 5 14,059 ±15 13,687 13,364

15.67 4 14,114±8 13,689 13,366

Gillespie, Lambert and Gibson

[356] NaCl 540

283 540

283

1081 567 20

20

11

1 13,773

13,793

13,516

13,545

13,349 13,333 550 550 1101 24.99 1 13,571 13,571 13,407 284 284 569 32.27 1 13,199 13,525 13,315 \ 282.5 282.5 566 32.27 1 13,261 13.588 13,376 260 260 521 32.30 1 13,271 13,596 13,377 Bender and Biermann [213] NaCl 18.42 18.42 37.84 25 2 14,249 ±12 14,249 13,332

17.14 17.14 35.30 25 4 14,314 ± 10 14,314 13.331

Pitzer [206] NaCl 46.5 1065.5 1112 25 3 13,823 ±12 13,828 13,366

40

e Heat of solution (at infinite dilution) values determined

by 26 investigators are compiled in Table 4.

Table A/T of NaCl in H20 at 25 °C (Ref. 2)

Investigator

1. Winkelmann (94]

2. Ostwald (443]

3. Thomsen (30]

4. Pickering [384]

5. Colson [535]

6. Randall and Bisson [143]

7. Wiist and Lange [21]

8. Lange and Durr [389]

9. Lipsett, Johnson, and Maass [323]

[5.%]

10. Cohen and Kooy [391]

11. Askew, Bullock, Smith, Tinkler, Catty, and Wolfenden [499]

12. Becker and Roth [228]

13. Lange and Martin [397]

14. Slansky [399]

15. Tichelaar [401]

16. Voskresenskaya and Ponomareva [400]

17. Fineman and Wallace [404]

18. Samoilov [407, 408]

19. Kapustinskii and Drakin [411]

20. Seki and Suzuki [537]

21. Benson and Benson [324]

22. Benson, Goddard, and Hoeve [538]

23. Attree, Cushing, Ladd, and Pieroni [539]

24. Lister and Myers [540]

25. Samoilov arid Buslaeva [444]

26. Criss and Cobble [541]

Year

reported

Temp of measNo. of measCone, range moles NaCl

/

lOOOg H2 0

AW:

1873 °C

16-30 20 5.50 to 0.53 cal/mole 914 ±30

1882 16-17 4 0.19 970

1883 16.8 2 .56 897 ±20

1887 15-25 35 .28 935 ±20

1915 21 1 .42 894

1920 25 1 .54 to 0.13 929 ±5

1925 25 14 5.62 to 0.52 3 931 ±10

1926 25 10 0.56 841 1927 25 20 5.50 to 0.07 923 ±5

1927 20 15 5.92 to 0.04 922 ±8

1928 25 4 0.56 915 ±5

20 5 .56 921 ±8

1934 20 9 .03 90*1 ±30

1935 19.7 5 .09 to 0.04 918 ±10

1937 25 1 .25 934

1940 25 ? 9 a 915 ±10

1946 25 5 0.02? 950 ±30

1946 25 ? .37 970

1948 25 ? 9 3 925 ±5

1951 25 1 0.19 932

1952 25 1 .0008 932 ±30

1953 18 ? .14 913 ±20

1955 25 16 1.3 to 0.05 928 ±3

1956 25 3 0.50 927 ±3

1958 25 9 .01 927 ±10

1958 25 9 .18 914 ±10

1960 15, 35 2 .14 874 ±100

1961 25 17 .02 to 0.001 914 ±10

* Authors’ extrapolation.

41

f . Solubility

1. At 1 atmosphere and temperatures from -10 to 107. 0°C

(boiling point) are presented in Table 5 (International

Critical Tables Ref. 3).

S'

Table Density of Saturated Sol utfo-js

Temp. Per Cent NaCI rc> by Weight in Soln -10 S0i.utfu.iYy 1.2000 0 26.34 1.2093 + 10 26.35 1.2044 20 26.43 1.1999

25 26.48 1.197S 30 26.56 1.1957 40 26.71 1.1914 50 26.89 1.1872 60 27.09 1 . 1830 70 27.30 1.1787 80 27.53 1.1745 90 27.80 1.1703

100 28.12 1.1660

107.0* 28.39 1.1631

• Boiling point.

42

2. At high temperatures

Tables 6a and 6b show results for solubility at high

temperatures. (Berkley (4), Tilden and Shenstone (5),

Froehlich, et al (6), Schoeder, et al (7), Brenrath,

et al (8), and Lill and Lindsay (9)

^ ft Table#. Solubility, Activity Coefficients, and Salt Activity for Saturated NaC! (Ref. 9)

Solutions

Temperature

<°C)

Solubility, ms (moles NaCI/kg II 2 O)

Activity

coefficient 7^ Inti

In ( 7yii s

) (footnote a

)

75 6 A 60 0.996 -0.0038 1 .86 1

S

100 6.680 0.935 -0.0676 1.8316

125 6.935 0.835 -0.1808 1.7558 150 7.198 0.721 -0.3270 1.6468

175 7.573 0.610 -0.4942 1.5305 200 7.973 0.501 -0.6914 1.3847 225 8.435 0.398 -0.9222 1.2101 250 8.989 0.303 -1.1951 1.0009 275 9.649 0.218 -1.5247 0.7421 300 1 0.4 1

3

0.144 -1.9375 0.4056

a Salt activity = ys

nis

.

Table Solubility in Aqueous Solution at High Temperatures (Ref. 18)

Temp. Per Cent by Weight CC) in Solution

100 2S.12

107* 28.39

150 29.7 200 31.6

250 34.1 300 37.3 350 41.8 400 46.4 450 50.8

* Boiling point at atmospheric pressure.

43

3. Effect of pressure on solubility was investigated by Adams

and Hall (10), who used resistance measurements , and i

in Table 7

.

Table m. Effect of Pressure on Solubility at 25°C

Pressure Grams NaCl Grams NaCl per Mole Per (atm) per 100 g Soln I00gH,O Cent of NaCl

0 26.42 35.91 9.97 250 26.59 36.22 10.05 500 26.74 36.50 10.12 750 26.88 36.76 10. IS 1000 27.01 36.99 10.24 1250 27.11 37.18 10.29

1500 27.20 37.37 10.33

shown

44

8- Activity coefficients have been evaluated by Wu and Hamer

at 25 °C (11) from an equation of the form:

lo8 7±

=

Z+Z

- A

m

I + Pi + Cl2 + DI

3

1 +

m

The results are shown in Table 8.

9

Table fm. Osmotic and cier

m 0 y 0.00] O.988 0.965

.002 .954 .952

.005 . -976 .928

.01 .968 .903

.02 •959 .872

.05 • 944 .822

.1 •933 119

.2 • 924 • 734

• 3 .921

' .709

.4 .920 .693

•5 .921 .681

.6 •923 .673

• 7 .926 .667

.8 .929 .662

•9 • 932 .659

3

* = 1.4495

6 = 2.0442 x 10”

C = 5-7927 x

10" 3

D = -2.8860 x io~

h

:tivity coelTicients of ib.Cl

n 0 y 1.0 O.936 0.657

1.2 • 944 .655 1.4 •953 .656 1.6 .962 . 658

1.6 • 973 . 662

2.0 • 984 .668

2-5 1.013 .6S8

3-0 1.045 • 714

3-5 1.080 .746 4.0 1.116 .783

4.5 1.153 .826

5.0 I.192 .C74

5-5 1.231 • 923

6.0 1.270 .986

0(0) = 0.00064

° (7) 0.00049

VAR(p) = 4.12 x O

1 -4

VAR( y) = 2.43 x 10~ {

o*(0) = 0.00066

o*{y) ~ 0.00063

45
;
From Robinson and Stokes (12) and Earned and Owen (13), mean activity

coefficients can be calculated over the temperature range 0-100°C

using an equation of the form:

log y

± = A - |

- C log T

Table 9 illustrates these results.

Temp. CC)

Table

0.1

9& Mean

0.2

Activity Coefficients

Molality

0.5 1.0 2.0 3.0 4.0 0 0.781 0.731 0.671 0.637 0.630 0.660 0.717

20 .779 .733 .679 .654 .665 .712 .783 40 .774 .728 .678 .657 .678 .728 .802 60 .766 .721 .671 .654 .676 .726 .799 80 .757 .711 .660 .641 .663 .712 .777 100 .746 .698 .644 .622 .641 .687 .746

Liu and Lindsay ( 9 ) have recently reported activity coefficients at

high temperatures as illustrated in Table 10.

IO

Table fP. Smoothed Activity Coefficients for NaCl

Temperature, °C

Molality 75 100 125 150 175 200 225 250 275 300

0.05 0.804 0.794 0.780 0.764 0.746 0.725 0.702 0.673 0.638 0.5 >-2 0.10 0.757 0.746 0.729 0.709 0.687 0.662 0.633 0.599 0.559 0.50'- 0.20 0.711 0.698 0.677 0.653 0.626 0.597 0.563 0.525 0.479 0.4 22 0.40 0.669 0.655 0.631 0.602 0.571 0.536 0.498 0.454 0.404 0.34 5 0.60 0.651 0.637 0.610 0.578 0.543 0.505 0.464 0.4 3 8 0.366 0.3 (!' 0.80 0.643 0.628 0.599 0.564 0.527 0.486 0.442 0.394 0.340 0 2 7 ; 3.00 0.640 0.624 0.594 0.557 0.517 0.474 0.428 0.378 0.323 0.261

1.50 0.645 0.627 0.592 0.550 0.505 0.457 0.406 0.352 0.294 0.231 2.00 0.661 0.641 0.601 0.553 0.503 0.450 0.394 0.337 0.276 0

.

2 \ 2 2.50 0.682 0.659 0.615 0.562 0.506 0.448 0.388 0.327 0.264 0.2' 0 3.00 0.709 0.682 0.632 0.573 0.512 0.449 0.385 0.321 0.256 0.141. 3.50 0.740 0.708 0.652 0.587 0.520 0.452 0.384 0.316 0.249 0.182 4.00 0.774 0.737 0.674 0.602 0.529 0.456 0.384 0.313 0.244 0.1 7o

4.50 0.812 0.769 0.698 0.619 0.539 0.461 C.385 0.31

1

0.239 0.17: 5.00 0.853 0.803 0.724 0.636 0.550 0.466 0.386 0.309 0.236 0.167

5.50 0.898 0.839 0.750 0.655 0.562 0.472 0.387 0.308 0.233 0.1 (-3 6.00 0.947 0.878 0.779 0.674 0.573 0.478 0.389 0.3(i7 0.230 0.!v i 6.50 - 0.919 0.808 0.693 0.585 0.484 0.391 0.306 0.228 0.157

7.00 _ — — 0.713 0.597 0.490 0.393 0.305 0.226 0. i 55 8.00 — — - - - - 0.396 0.304 0.223 0. 1 5 1 9.00 - - - - - - - - 0.220 0.

1

-I s 10.00 - - - - - - - - (1.14 5

h. Osmotic coefficients

Values of the osmotic coefficients taken from references

11, 12, 13, 9, above have been listed in Table 8 (25°C)

and Table 11 (75-300*0).

1 ! Table SI. Smoothed Gsmotie Coefficients for NaCl

Temperature, °C

Molality 75 100 125 150 175 200 225 250 275 300

0.05 0.938 0.934 0.929 0.923 0.915 0.907 0.897 0.884 0.868 0.846

0.10 0.926 0.922 0.915 0.907 0.897 0.886 0.873 0.857 0.S37 0.809

0.20 0.917 0.913 0.904 0.R94 0.882 0.868 0.852 0.832 0.S06 0.772

0.40 0.916 0.912 0.902 0.889 0.874 0.857 0.837 0.812 0.781 0.7-.U 0.60 0.922 0.917 0.907 0.892 0.876 0.856 0.833 0.S06 0.771 0.725

0.80 0.930 0.926 0.914 0.899 0.880 0.859 0.834 0.804 0.766 0.717

1.00 0.940 0.936 0.923 0.907 0.887 0.864 0.837 0.805 0.765 0.713

1.50 0.967 0.962 0.948 0.929 0.906 0.879 0.848 0.812 0.767 0.70V

2.00 0.996 0.990 0.974 0.952 0.926 0.896 0.862 0.S21 0.772 0.7ii9 2.50 1.026 1.018 1.000 0.975 0.947 0.914 0.876 0.831 0.778 0.71 1 3.00 1.057 1.046 1.025 0.998 0.967 0.930 0.889 0.841 0.784 0.714

3.50 1.088 1.075 1.051 1.020 0.986 0.946 0.902 0.S51 0.79 I 0.718

4.00 1.120 1.103 1.076 1.042 1.004 0.962 0.914 0.860 0.797 0.72: 4.50 1.152 1.131 1.100 1.063 1.022 0.976 0.925 0.868 0.803 0.725 5.00 1.184 1.159 1.124 1.083 1.038 0.990 0.936 0.S76 0.S09 0.728

5.50 1.216 1.187 1.147 1.103 1.054 1.002 0.946 0.884 0.814 0.732

6.00 1.249 1.215 1.170 1.121 1.069 1.014 0.955 0.890 0.819 0.756

6.50 - 1.242 1.193 1.139 1.083 1.025 0.963 0.896 0.823 0.759

7.00 — - - 1.157 1.097 1.035 0.970 0.901 0.827 0. / -4 ? 8.00 - - - - - - 0.982 0.910 0.834 0.750

9.00 - - - - - - - - 0.839 0.75 7 10.00 - - - - - - - - - 0.?...:

47

1 Vapor pressures taken from the International Critical Tables

(3) are shown in Table 12.

&

Table SI, Vapor Pressures of Aqueous Solution's in mm Hg

i o

0.0 2.5 S 7.5 10 12.5 15.0 17.5 20.0 22.5 25.0 27.5

0 4.579 4.5 4.4 4.4 4.3 4.2 4.1 4.0 3.8 3.7 3.5

III 9.2! 9.1 8.9 8.8 8.6 8.4 8.2 8.0 7.7 7.4 7.1 20 17.54 17 3 17.0 16.7 16.4 16.1 15.7 15.3 14.8 14.2 13.6

.10 31.83 31.4 30.9 30.4 29.8 29.2 28.5 27.7 26.8 25.8 24.7

10 55.34 54.5 53.6 52.7 51.7 50.7 49.5 48.1 46.6 44 9 43.0 50 92.54 91.2 89.7 88.1 86.4 84.7 82.8 80.5 78.1 75.3 72.2 60 149.46 147.2 144.8 142.3 139.7 136.8 133.7 130.0 126.0 121.7 116.8

70 233.79 230.2 226.4 222.4 218.3 213.9 208.9 203.5 197.5 190.7 183.1 SO 355.47 350 344 338 332 325 318 309.5 300.5 290.2 278.9 266

00 526.00 517 509 500 491 481 470 458 •145.1 430 414 395

100 760.00 748 736 723 710 695 680 665 643 622 599 572 no 1074.5 1057 1940 1022 1003 983 961 936 911 88! 849 810 H P.,°C 100.0 100.44 100.90 101.40 101.93 102.51 103.16 103.89 104.72 105.68 106.78 108.12

j. Apparent molal volumes are given in Table 13 as determined

by Wade (14)

.

Table If. Apparent Molal Volume in Aqueous Solution

Molality Apparent Molal Volume </> in cm’ 0 16.40*

0.1 16. 68

0.2 16.88 0.3 17.05 0.4 17.20 0.5 17.35 0.75 17.67

1.0 17.97

* This extrapolated value also gives the partial molal volume in infinitely dilute solution.

48

k. Partial molal volumes recently reported by Millero (15) are

shewn in Table 14.

Table

Salt

F° (cm3 /mole)

by Sy* [cm3

liter mole-2

] [cm3

liter Y* mole - *

8

] References

NaCI 16.61 0.018 20,55,104

16.62 0.048 22

16.62 -0.03 16 16.63 (0.003) 50

16.61 56

16.65 34

16.64 57 16.60 58

16.6 5 16.67 45

16.62 1.884, 1.853

26,113

16.61 51 16.8 9

15.9 9

17.03 59

16.54 43

16.8 52

16.28 2.22 53

16.28 2

16.40 2.153 3 16.35 60

16.44 61

16.3 6

16.56 1.945 62

16.78 111 16.45 1.693“ 0.405“ 100

49

1. Compressibility has been investigated by Gibson (16) and

is illustrated by Table 15.

^ /r

Table Compressibility of Solutions

Weight

Per Cent

in Soln

$ x so» From Compressions

at 1000 Bars

sxio*

From Sound Velocities at 1 Bar 6 40.6 40.4

10 37.6 37.5

16 33.2 33.4

20 30.7 31.0

24 28.4 28.8

m. Eutectic of solution . The eutectic composition is 30.4 g

NaCl(anhyd.) per 100 g with the temperature being

-21.12°C, Rodebush (17).

n. Freezing point lowering from International Critical Tables (3)

are presented in Table 16.

Table jp. Freezing Point Lowering of Sodium Chloride Solutions

Molality Grams Anhydrous Molal F.P. F.P. Lowering

Salt per 1000 g Water Lowering (°C) 0.001 0 . 05S5 3.66 0.004

.002 .1169 3.65s .007

.004 .2338 3.642 .015

.007 .4091 3.620 .025

.01 .5845 3.604 .036

.02 1.1690 3.570 .071

.04 2.3379 3.530 .141

.07 4.0914 3.498 .245

.10 5.844S 3.478 .34S

.20 11.6896 3.424 .685

.40 23.3792 3.38 1.35

.70 40.9136 3.36 2.35

1.0 58.448 3.37 3.37 2.0 116.S96 3.45 6.90

3.0 175.344 3.60s 10. S2

4.0 233.792 3.78s 15.14 5.20* 303.9296 4.061 21.12

* Eutectic.

50

o. A phase diagram taken from Kaufmann (18) is shown as Figure 1

0% NoCI *«.?•!> S«.SS» 100% M«CI

100% HgO T«.®» S8.ISF 0% M,0 C9«mmca

Figure 1. The system sodium chloride-water (Not to scale)

51

p. Density of solutions from 0 to 100°C are available frotu

the International. Critical Tables (3) and are illustrated

in Table 17

.

Per Cent by

Weight in Soln

1 1 2 1 4 1 6 1 8 1 10 1 12 1 14 1 16 1 15 1 20 1 22 1 24 1 26 1

Table aDensity of Sodium Chloride Solutions

Temp.

0°C

.0074711.

.0150911.

. 0303S 1

.

.04575

.06121 .07677

.09244

. 10S24 1

io°c

00707 1 01442 1 0292011

04-10S; 1 0590711 07419 1 0S946; 1 10491:1

20°C

. 00534Jl

. 01.246| 1 .02680'! .04127,1

. 055S9j 1 0706S; 1 .08566 1

. 100S51

25°C 30° C

0026110. 00957,1.

0236111.

. 03963} 1 . 03731 i 1 .05412 1 .05219! 1

.

.06879' 1 .06676: 1

.

0S15s! 1

.

09651 1.

.00409 1.

. 01112, 1 . .02530,1.

>;i 08365 ! 1

.

09S721

40°C 1-

9990SI0.

00593j 1. 01977! 1. 03378j 1. 04798 1

.

0623811. 07699, 1. 09182'!.

5Q°C ! 60°C

99482 0 00161 0. 015311.

02919 1. 04326 1. 05753 i

.

07202 1 08674 i.

9900 0. 9907 0. 0103 0. 0241 1. 03S1 j 1

.

0523 1

.

0667 1. 0813 1.

80°C —r9785 0 98520

9988 0 0125 0

0264:1 0405 1 0549 1 0694 1

ioo°C

9651 9719

9855

9994 0134

0276

0420

0565

. 12419,1 . 12056 1.11621 1 . 11401 1 . 11171 1 . 10688 1 . 10170 1 .0962 1 .0842 1 .0713

. 14031 1 1 . 13643 l . 13190, 1 . 12954 1 1 . 12715] 1 . 12218 1 . 1 1691 1.1113 1. 0993: 1 . 0S64

. 15663] 1 . 15254,1 . 14779,1 . 14533: 1 . 14285,1 . 13774] 1 . 13238,1 . 126S 1 . 1 146 1 . 1017

. 17318] 1 . 16891

1 1 . 16395] 1 . 16140| 1 . 158831 1 . 153581 1 . 14812 1 . 1425 1 . 1303] 1 . 1 172

. 18999,1. 1S557I1. 18040, 1.17776|1. 1751l| 1.16971S1. 16414 1 . 1584 1 . 1463 1 . 1331

.2070911 .20254] 1 . 19717 1 . 19443:1 . 19170 1 . 186141 . 18045 1 . 1747 1 . 16261 . 1492

I I I I

I I

I

1 I

52

3. Transport and Other Properties

A listing of transport and other properties which should

be included in such a monograph on aqueous sodium chloride is shown

for completeness. Whether these properties can be included, will

depend on the manpower available for such a task.

Boiling points of saturated solutions 760 mm.

Conductivity

Decomposition potential

Density

Density of saturated solutions

Dielectric constant at low temperatures

Diffusion coefficient

Ionic conductance

Refractive Index

Surface Tension

Thermal conductivity

Transference number

Velocity of sound

Viscosity

53

References for Appendix 3

1. Rossini, F. D. , Wagroan, D. D. , Evans, W. H. , Levine, S., and Jaffe, I.,

Selected Values of Chemical Thermodynamic Properties, Nat.

Bur. Standards (U.S.), Circ. 500, 2, 3 (1952 ) f and revisions.

2. Parker, V. B. , Thermal Properties of Aqueous Uni-univalent Electrolytes NSRBS-NBS-2, U.S. Gov't Printing Office, Washington, D.C

.

20402, 1965.

3. "International Critical Tables of Numerica 1 Data , Physics, Chemistry,

and Technology", New York, McGraw-Hill Book Company, Inc., 1928.

4. Berkeley, Earl of, Trans. Roy. Soc. (London), A. 173, 428 (1939).

5. Tilden, W. A., and She ns tone , W. A., Trans. Roy. Soc. (London),

A. 175, 23 (1884)

.

6. Froehlich, W. , Mitt. Kali Forsch. Anstalt GmbH. 68, 37 (1929).

7. Schroeder, W. C., Gabriel, A., and Partridge, E. P, , J. Am. Chem.

Soc., 57, 1539 (1935).

8. Jessup, R. S. , Refrig. Eng., 39, 100 (1910).

9. Liu, C. and Lindsay, W. T., J. Solution Chem. , JL, 45 (1972).

10. Adams

,

L. H., and Hall, R. E., J. Wash. Acad. Sci. 21, 183 (1931).

11. Wu, Y. C. and Hamer, W. J., J. Phys . and Chem. Ref. Data, 1972, in

12.

Robinson, R. A. and Stokes, R. H. , Electrolyte Solutions, 2nd ed.,

Butterworths, (London) (1959).

13. Harned, H. S, and Owen, B. B., The Physical Chemistry of

Electrolytic Solutions, 2nd ed., New York, Reinhold Publishing

Corporation, (1950)

.

14. Wade, E. B. H. , J. Chem. Soc., 75, 254 (1899).

15. Millero, F. from Horne, R. A., ed., Water and Aqueous Solutions-

Structure, Thermodynamics, and Transport Properties, WileyInterscience, Div. of John Wiley and ons, Inc., New York, 1972.

16. Gibson, R. E., J. Am. Chem. Soc., 57, 284 (1935).

54

17. Rodebush, W. H.

00 s=H Kaufmann, D. W.

1960.

J. Am. Chem. Soc. 40, 1204 (1918).

Sodium Chloride, Reinhold Pub. Corp., New York,

55

Appendix 4.

Scope of Current Literature on Electrolyte Data

Several surveys of the literature on electrolyte data were made

in order to adequately assess the extent and types of data on electrolyte solutions available in primary and secondary reference sources. A number of different approaches were used to obtain a good

estimate of the types and amount of data appearing in the current

literature. The Bulletin of Thermodynamics and Thermochemistry (1971)

was one source of information using articles on inorganic compounds only.

Another source was the Chemical Abstracts, Physical Sections only

(1971). Issues covering a two month period were scanned as part of an

abstracting process. A third source was Chemical Titles (1972).

Here, only entries with "Solution" contained in the title, were scanned.

From these three different types of literature scanning the total

number of articles currently appearing per year were estimated to be

nearly 500 articles that dealt with electrolyte solutions of all types.

Three broad categories could be discerned from the collection

of current literature: (1) Single electrolytes in water, (2) Ternary

and mixed electrolytes in water, and (3) Non-aqueous systems, including

single and mixed electrolytes. Properties of the single electrolytes

in water were further subdivided into the thermodynamic properties and

the transport properties. This was not done for the other categories.

Table I depicts the approximate annual rate of appearance of current

literature for electrolyte solutions.

56
\
Table I. Rate of Appearance of Current Literature

for Electrolyte Solutions

Single electrolytes in pure water including

transport properties 200 articles per year

without transport properties 125 f ? n n

Mixed electrolytes 200 It h »f

Non-aqueous solutions 80 If M M

57


iii