Handbook of chemistry and physics, 96th edition dr soc

Mickey draws heavily on the thermodynamic and thermophysical property data experts at the National Institute of Standards and Technology NIST, and he is committed to including uncertaint

Editor-in-Chief

W M Haynes, Ph.D

Scientist Emeritus National Institute of Standards and Technology

Associate Editor

Thomas J Bruno, Ph.D

Group Leader National Institute of Standards and Technology

Editor, Internet Edition

Lev I Berger

California Institute of Electronics and Materials Science

Dana L Roth

Millikan Library California Institute of Technology

Michael Frenkel

National Institute of Standards and Technology

Daniel Zwillinger

Mathematics Department Rensselaer Polytechnic Institute

Robert N Goldberg

National Institute of Standards and Technology

I bought my first copy of the CRC Handbook of Chemistry and

Physics in the fall of 1956 as a freshman engineering student at

University of California, Los Angeles (UCLA) I remember trying to

shortcut the chem 1 lab experiments by doing flame tests to identify

the elements (rather than the tedious correct procedure) using the

tables from the Rubber Handbook Somehow I made an egregious

mistake and the lab TA quizzed me, asking how I could have made

such gross errors in my analysis I got a zero on that experiment

Later in my freshman year, I ran out of money and had to drop

out for six months, working as a tool designer for Douglas Aircraft

Company What I remember is using some tables from the

Handbook as I was trying to use the Young’s modulus and other

properties to estimate the sizes of aluminum alloy tubes for the

pressure tests on the Navy A3D fighter (my “tool” was designed to

contain the damage if the cockpit failed the pressure test)

I do not remember using the Handbook much as I finished my

B.S in engineering at UCLA, nor do I remember the first few

years as an engineering science graduate student studying

metal-lurgy at the California Institute of Technology (Caltech)

However, after obtaining my Ph.D in October 1964 and joining

the chemistry faculty at Caltech in November 1964, I began trying

to find the best data on bond energies, heats of formation,

ion-ization potentials, electron affinities, elastic moduli, and so forth,

so that I could compare the quantum mechanics calculations

based on the method (generalized valence bond) I had developed

as a graduate student Here, I lost confidence in the Handbook

because some of the data were ancient and some more modern,

but generally, there were no references to the data, so I could not

check the reliability

As a result, I built my own reference system with the best

ther-mochemical data from various references but supplemented by

using Sid Benson group additivities, whose tables I extended with

my QM studies I kept track of tabulations in various critical

analy-sis journals (Landolt Börnstein, JANAF, J Chem Phys Ref Data),

and review articles (Hotep and Lineberger electron affinities),

and compared discrepancies in the data from different sources

by referring back to the original papers In those days, I would

often spend Sunday in the Millikan Library at Caltech updating

my properties databases, sometimes receiving assistance from the

chemistry librarian at Caltech, Dana Roth (who started graduate

school in chemistry at Caltech the same year I started in

engineer-ing science) Dana was always able to find the missengineer-ing data

However, this all changed when David Lide became the editor

of the Handbook Quickly the old unreferenced data was replaced

with critically reviewed data, citing the original references Thus,

I could check to see if the latest references I knew about had been included As a result, I no longer maintained my own reference li-

brary, knowing that I could find it in the Handbook and that I could

trust the data When in doubt, I could find the reference and check the original source I am pleased that this policy has continued under Mickey Haynes, the present editor Mickey draws heavily

on the thermodynamic and thermophysical property data experts

at the National Institute of Standards and Technology (NIST), and

he is committed to including uncertainty values and references to original data sources, a very important addition

As my research interests have broadened and changed over the last five decades, the kind of theory that I do has changed as to how I obtain data and the kind of data that I need However, when-ever I need to find a particular heat of formation, redox potential,

or melting point, I know exactly where to go

I am pleased that CRC has evolved to make the database able and on the web for easy access This is so much better than

search-in the old days

I am honored to participate this year in the progress of this great institution and expect that it will continue to evolve to serve the science and technology community as we begin to focus more on energy and water sustainability to serve the continually expanding population of the world

I do have a suggestion for the future Computational methods have improved to the point that for many areas of science and technology the quantities predicted from the theory can be trusted

as much as the experiments, particularly for properties involving

interfaces and surfaces I strongly recommend that the Handbook

start to investigate how to include such information This is very complicated because there are a variety of methods and approxi-mations so that informed judgments must be made about how much to trust any particular predicted data The experts know (usually), but we need to provide for nonexperts curated computa-tional data including estimates of its reliability

William A Goddard III

Charles and Mary Ferkel Professor of Chemistry, Materials

Science, and Applied PhysicsDirector, Materials and Process Simulation Center (MSC)

California Institute of TechnologyPasadena, California 91125 USAE-mail: wag@wag.caltech.edu

January 2015

highlighting the achievements of some of the major historical figures in chemistry and physics was initiated with the 94th edition This series is continued with this edition which is focused on Lord Kelvin, Michael Faraday, John Dalton, and Robert Boyle This series, which provides biographical information, a list of major achievements, and notable quotations attributed to each of the renowned chemists and physicists, will be continued in succeeding editions Each edition will feature two chemists and two physicists The following new tables have been added to this edition:

Section 1: Basic Constants, Units, and Conversion Factors

• Descriptive Terms for Solubility

Section 8: Analytical Chemistry

• Stationary Phases for Porous Layer Open Tubular Columns

• Coolants for Cryotrapping

• Instability of HPLC Solvents

• Chlorine-Bromine Combination Isotope Intensities

Section 16: Health and Safety Information

• Materials Compatible with and Resistant to 72 Percent Perchloric Acid

• Relative Dose Ranges from Ionizing Radiation

Significant updates and expansions of tables for the 96th Edition include the following:

Section 6: Fluid Properties

• Update and expansion of Sublimation Pressure of Solids

• Major update of Vapor Pressure of Fluids at Temperatures Below 300 K

Section 7: Biochemistry

• Expansion of Structure and Functions of Some Common Drugs

Section 8: Analytical Chemistry

• Minor update of Nuclear Spins, Moments, and Other Data Related to NMR Spectroscopy Section 9: Molecular Structure and Spectroscopy

• Update of Bond Dissociation Energies

Section 11: Nuclear and Particle Physics

• Update of Summary Tables of Particle Properties

• Major update of Table of the Isotopes

Section 14: Geophysics, Astronomy, and Acoustics

• Update of Major World Earthquakes

• Update of Atmospheric Concentration of Carbon Dioxide, 1958-2014

• Update of Global Temperature Trend, 1880-2014

Section 15: Practical Laboratory Data

• Update of Dependence of Boiling Point on Pressure

Section 16: Health and Safety Information

• Update of Threshold Limits for Airborne Contaminants

Appendix B:

• Update of Sources of Physical and Chemical Data

In addition to offering the full text of the print edition in searchable pdf format, this Internet Version

2016 presents the major tables of numerical data in the form of interactive tables that can be sorted, filtered, and combined in various ways Substances in these tables can be retrieved by searching on name,

for a desired property Thus, one can request a specific property of a specific substance (for example, viscosity of benzene as a function of temperature) and receive a customized table with exactly that information In addition, the Internet version includes a section with pdf files of many older tables that have been removed from the print edition to make space for new material

The success of the Handbook is very dependent on feedback from its users The Editor-in-Chief appreciates any suggestions from readers on proposed new topics for the Handbook or comments on how the usefulness of the Handbook may be improved in future editions Please send your comments to the

Editor-in-Chief: william.haynes@taylorandfrancis.com

Numerous international experts make key contributions to the Handbook These contributors are

listed on pages immediately following the Preface Their efforts play a key role in the quality and

diversity of the subject matter covered in the Handbook I also acknowledge the sound advice and guidance of the Editorial Advisory Board members of the Handbook, who are listed in the front matter

Fiona Macdonald, Publisher – Chemical & Life Sciences, CRC Press/Taylor & Francis Group has been of great assistance and support in providing oversight to ensure that the Handbook continues to satisfy the needs of the user community Thanks also to Linda Leggio, Pam Morrell, Theresa Gutierrez, and James

Yanchak for their detailed, cooperative work and extreme care in the production of the Handbook

W M Haynes

March 2015

Toni F Haynes, and members of my family, Michael and Am Haynes, and to my granddaughter, Amelia Suwan Haynes

How to Cite this Reference

The recommended form of citation is: W M Haynes, ed., CRC Handbook of Chemistry and Physics, 96th Edition (Internet Version 2016), CRC Press/Taylor and Francis, Boca Raton, FL If a specific table

is cited, use the format: "Physical Constants of Organic Compounds," in CRC Handbook of Chemistry and Physics, 96th Edition (Internet Version 2016), W M Haynes, ed., CRC Press/Taylor and Francis,

Boca Raton, FL

This work contains information obtained from authentic and highly regarded sources Reprinted material is quoted with permission, and sources are indicated A wide variety of references are listed Best efforts have been made to select and verify the data on the basis of sound scientific judgment, but the author and the publisher cannot accept responsibility for the validity of all materials or for the consequences of their use

© Copyright Taylor and Francis Group LLC 2016

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Born: Woolsthorpe, Lincolnshire, England, December 25, 1642Died: London, England, March 20, 1727

Fellow of Trinity College of Cambridge University

• His monograph Philosophiæ Naturalis Principia Mathematica (commonly known as Principia), published in 1687, laid the foundation for most of clas-

sical mechanics In this work, Newton described the law of universal

gravita-tion and the three laws of mogravita-tion The Principia is generally considered to be

one of the most important scientific books ever written

• Built the first practical reflecting telescope and developed a theory of color based on the observation that a prism decomposes white light into the many colors that form the visible spectrum and that a lens and a sec-ond prism could recompose the multicolored spectrum into white light;

“If I have seen further it is by standing on the shoulders of giants.”

“I do not know what I may appear to the world, but to myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.”

Born: Copenhagen, Denmark, October 7, 1885Died: Copenhagen, Denmark, November 18, 1962Chair of Theoretical Physics at the University of Copenhagen

• Received the Nobel Prize in Physics in 1922 “for his services in the tion of the structure of atoms and of the radiation emanating from them.”

investiga-• Developed the model of the atom with the nucleus at the center and trons in orbit around it, which he compared to the planets orbiting the sun

elec-• Developed the idea that electrons move from one energy level to another in discrete steps, which became a basis for quantum theory

• Conceived the principle of complementarity: that things may have a dual nature, but we experience only one aspect at a time, for example, light can behave as either a wave or a stream of particles depending on the experimental framework

• Part of the British team of physicists working on the Manhattan Project; became an advocate of the peaceful use of nuclear energy; received the first ever Atoms for Peace Award in 1957; one of the founding fathers of CERN in 1954

• A chemical element (number 107) named in honor of Bohr; hafnium, ment number 72, whose properties were predicted by Bohr, was named

ele-by him after Hafnia, Copenhagen’s Latin name

• Centennial of the Bohr model commemorated in Denmark this year (2013)

“An expert is a man who has made all the mistakes which can be made, in a

very narrow field.”

“Anyone who is not shocked by quantum theory has not understood it.”

Antoine L Lavoisier French chemist

Born: Paris, France, August 26, 1743Died: Paris, France, May 8, 1794Member of the French Academy of Sciences

• Known as the “Father of Modern Chemistry.”

• Established the law of conservation of mass from combustion ments in discovering that, although matter may change its form or shape, its mass always remains the same

experi-• In Methods of Chemical Nomenclature (1787), he invented the system of

chemical nomenclature still largely in use today

• Named both nitrogen (1778) and hydrogen (1783) and predicted silicon (1778)

• Demonstrated that air is a mixture of gases (primarily oxygen and gen), one of which combines with metals to form oxides; demonstrated oxygen’s role in animal and plant respiration

nitro-• Determined that the components of water are hydrogen and oxygen

• Was the first to establish that sulfur was an element (1777) rather than a compound

• Helped to construct the metric system and compiled the first extensive list of elements

• Disproved the phlogiston theory, which postulated that materials leased a substance called phlogiston when they burned

re-• Introduced the possibility of allotropy in chemical elements when he ered that diamond is a crystalline form of carbon

discov-• Introduced a rigorous experimental approach to chemistry based on the termination of the weights of reagents and products of chemical reactions

de-• Was beheaded during the French revolution

“A man cannot live more than 24 hours unless he has at least three cubic

meters of air that is being constantly replaced.”

“I consider nature a vast chemical laboratory in which all kinds of sition and decompositions are formed Vegetation is the basic instrument

compo-the creator uses to set all of nature in motion.”

Born: Tobol’sk, Siberia, Russia, February 7, 1834Died: St Petersburg, Russia, February 2, 1907Professor of Chemistry at Saint Petersburg Technological Institute and Saint Petersburg State University; Director of the Bureau of Weights and Measures

• Author of the definitive chemistry textbook of his time called The Principles of Chemistry written in Russian (1870).

• Generally given credit for discovery of the Periodic Table, published in 1871; identified gaps in the table that were later filled with the discovery

of the missing elements

• Almost won the Nobel Prize in Chemistry in 1906 (lost by one vote)

• In 1955, a newly discovered element (number 101) was named in his honor

“Work, look for peace and calm in work: you will find it nowhere else.”

“The establishment of a law, moreover, does not take place when the first thought of it takes form, or even when its significance is recognised, but only when it has been confirmed by the results of the experiment.”

Born: Pisa, Italy, February 15, 1564Died: Arcetri, Italy, January 8, 1642Chair of Mathematics at University of Pisa and University of Padua

• Known as the “Father of Modern Observational Astronomy,” the

“Father of Modern Physics,” the “Father of Science,” and “the Father of Modern Science.”

• Formulated the basic law of falling bodies in that the speed of falling ies is independent of mass, which he verified by careful measurements

bod-• Constructed and perfected the use of a telescope with which he ied lunar craters and mountains, and discovered four moons revolving around Jupiter, sunspots, and the phases of Venus

stud-• Gave credence to Copernicus’s claims that the Sun was the center of the universe (heliocentrism), and not the Earth

• Charged with heresy by the Inquisition of Pope Urban VIII in 1633 and imprisoned because he taught the public that the Earth revolved around the sun He was put under house arrest for the rest of his life

While under house arrest, he wrote Two New Sciences which

summa-rized his earlier work on kinematics and strength of materials

“Measure what is measurable, and make measurable what is not so.”

“Nature is relentless and unchangeable, and it is indifferent as to whether its hidden reasons and actions are understandable to man or not.”

“In questions of science, the authority of a thousand is not worth the

humble reasoning of a single individual.”

“I have never met a man so ignorant that I couldn’t learn something

from him.”

Born: Edinburgh, Scotland, November 13, 1831Died: Cambridge, England, November 5, 1879Chair of Natural Philosophy at Marischal College, Aberdeen and King’s College London; first Cavendish Professor of Physics at the University of Cambridge

• Produced a set of equations, known as ‘Maxwell’s Equations’ that plain the properties of magnetic and electric fields and help show that light is an electromagnetic wave

ex-• Awarded a prize in 1859 for his essay ‘On the Stability of Saturn’s Rings’, which described the nature of Saturn’s rings as numerous small par-ticles rather than a solid or fluid ring

• Developed the Maxwell–Boltzmann distribution, a statistical means of describing aspects of the kinetic theory of gases

• Regarded as the 19th-century scientist having the greatest influence on 20th-century physics; his work laid the foundation for special relativity and quantum physics

“All the mathematical sciences are founded on relations between physical laws and laws of numbers, so that the aim of exact science is to reduce the problems of nature to the determination of quantities by operations

with numbers.”

“The true logic of this world is the calculus of probabilities.”

Marie Sklodowska Curie Polish-French chemist and physicist

Born: Warsaw, Poland, November 7, 1867 Died: Haute Savoie, France, July 4, 1934Professor of Physics at the Sorbonne; Director of French Radium Institute

in Paris

• First famous woman scientist (known as “Mother of Modern Physics”)

in the modern world

• Awarded the Nobel Prize in Physics in 1903 with Pierre Curie (her band) “in recognition of the extraordinary services they have rendered

hus-by their joint researches on the radiation phenomena discovered hus-by Professor Henri Becquerel.”

• Awarded the Nobel Prize in Chemistry in 1911 “in recognition of her services to the advancement of chemistry by the discovery of the ele-ments radium and polonium, by the isolation of radium and the study

of the nature and compounds of this remarkable element.”

• First woman awarded a PhD in research science in Europe; first woman professor at the Sorbonne

• First woman to be awarded a Nobel Prize; first person to win Nobel Prizes in two different scientific disciplines

• Laid the foundation for radiation therapy for treatment of cancer; tributed to World War I efforts by setting up radiology units in clinics and hospitals throughout Paris and developing X-ray techniques used

con-in mobile units called “petit curies” con-in the field

“Nothing in life is to be feared, it is only to be understood Now is the

time to understand more, so that we may fear less

“I have frequently been questioned, especially by women, of how I could reconcile family life with a scientific career Well, it has not been easy.”

“Be less curious about people and more curious about ideas.”

“I consider nature a vast chemical laboratory in which all kinds of position and decompositions are formed Vegetation is the basic instru-

com-ment the creator uses to set all of nature in motion.”

Linus Carl Pauling American chemist, biochemist, peace activist, author, and educator

Born: Portland, Oregon, United States, February 28, 1901 Died: Big Sur, California, United States, August 19, 1994 Professor of Theoretical Chemistry at California Institute of Technology

• Awarded the Nobel Prize in Chemistry in 1954 “for his research into the nature of the chemical bond and its application to the elucidation of the structure of complex substances.”

• Awarded the Nobel Peace Prize in 1962 for his opposition to weapons

of mass destruction

• Only person to have won two unshared Nobel prizes

• One of the founders of quantum chemistry and molecular biology

• Introduced the concepts of electronegativity and orbital hybridization

• Named one of the 20 greatest scientists of all time by the New Scientist,

with Albert Einstein being the only other scientist from the 20th century

• His studies of hemoglobin led to the classification of sickle cell anemia

“Science is the search for truth, that is the effort to understand the world:

it involves the rejection of bias, of dogma, of revelation, but not the

rejection of morality.”

Born: Belfast, Ireland, June 26, 1824Died: Largs, Scotland, December 17, 1907Professor of Natural Philosophy at the University of Glasgow

• Determined the value of absolute zero as 273.15 ºC

• Developed forms of the first and second laws of thermodynamics

• Had an additional career as an electric telegraph engineer and inventor; knighted by Queen Victoria for his work on the transatlantic telegraph project

• First UK scientist to be elevated to the House of Lords; the name

“Kelvin” refers to the River Kelvin which flows close to his laboratory at

• Unit of kelvin for absolute temperature named in his honor

• Collaborated with James Joule to discover the Joule–Thomson effect that describes changes in the temperature of a gas that is expanded through a throttling valve

• Elected first president of the International Electrotechnical Commission

in recognition of his contributions to electrical standardization

“If you cannot measure it, then it is not science.”

“Accurate and minute measurement seems to the non-scientific imagination, a less lofty and dignified work than looking for something new But nearly all the grandest discoveries of science have been but the rewards of accurate measurement and patient long-continued labour in

the minute sifting of numerical results.”

“Let nobody be afraid of true freedom of thought Let us be free in thought and criticism; but, with freedom, we are bound to come to the conclusion that science is not antagonistic to religion, but a help to it.”

Born: Eaglesfield, Cumberland, England, September 6, 1766Died: Manchester, England, July 27, 1844

Member of the Manchester Literary and Philosophical Society

• Pioneering work in the development of modern atomic theory that evolved from his meteorological studies

• First person to study color blindness; his discovery became known as

“Daltonism,” which became the name for color blindness

• Known for the law of multiple proportions and the law of partial sures (known as Dalton’s law)

pres-• Unit of dalton to denote one atomic mass unit was named in honor of him; inorganic section of UK’s Royal Society of Chemistry is named after Dalton (Dalton Division) and the Society’s journal for inorganic

chemistry also bears his name (Dalton Transactions).

“Matter, though divisible in an extreme degree, is nevertheless not infinitely divisible That is, there must be some point beyond which we cannot go in the division of matter I have chosen the word ‘atom’ to

signify these ultimate particles.”

“I was introduced to Mr Davy, who has rooms adjoining mine (in the Royal Institution); he is a very agreeable and intelligent young man, and

we have interesting conversation in an evening; the principal failing in his character as a philosopher is that he does not smoke.”

Michael Faraday English chemist and physicist

Born: Newington Butts, England, September 22, 1791 Died: Hampton Court, Middlesex, England, August 25, 1867Professor of Chemistry at the Royal Institution of Great Britain

• Discovered electromagnetic induction in 1831, the principle behind electric transformers, generators, and electric motors; developed the concept of a field to describe electric and magnetic forces

• Provided the experimental and a good deal of the theoretical tion upon which Maxwell developed classical electromagnetic theory

founda-• First scientist to succeed in liquefying a permanent gas (carbon dioxide, chlorine)

• Unit of farad for capacitance named in his honor

• Received little formal education; developed a strong relationship with Sir Humphrey Davy after attending his lectures; established a reputa-tion as the outstanding scientist lecturer of his time

• Responsible for coining familiar terms in electrochemistry such as trode, cathode, anode, and ion

elec-• Discovered the laws of chemical electrodeposition of metals from tions

solu-• Discovered a number of new organic compounds, including benzene

• Inventor of the Faraday Cage, used to protect electronic equipment from lightning strikes and electrostatic discharges; radio frequency de-vices use Faraday Cages to prevent electromagnetic interference

“Nothing is too wonderful to be true, if it be consistent with the laws

of nature.”

“The lecturer should give the audience full reason to believe that all his powers have been exerted for their pleasure and instruction.”

Born: Lismore, County Waterford, Ireland, January 27, 1627 Died: London, England, December 31, 1691

Founder of the Royal Society of London

• Best known for Boyle’s law which describes the inverse relationship tween the absolute pressure and volume of a gas at constant tempera-ture

be-• Became known as the founder of modern chemistry; one of the neers of the modern experimental method; his work had a strong influ-ence on Sir Isaac Newton

pio-• Devoted much of his time to theology; promoted the spread of Christianity in the East; contributed to missionary societies; helped to translate the Bible into various languages

• Founded the Royal Society of London which still exists as the oldest continuous scientific society in the world

• First prominent scientist to perform controlled experiments and lish his work with details concerning procedures, apparatus, and obser-vations (results)

pub-• The phrase “chemical analysis” was coined by him

“I look upon experimental truths as matters of great concernment to

mankind.”

“If the omniscient author of nature knew that the study of his works tends to make men disbelieve his Being or Attributes, he would not have given them so many invitations to study and contemplate Nature.”

National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8420, USA

This report gives the 2010 self-consistent set of values of the basic constants and conversion factors of physics andchemistry recommended by the Committee on Data for Science and Technology (CODATA) for international use.The 2010 adjustment takes into account the data considered in the 2006 adjustment as well as the data that becameavailable from 1 January 2007, after the closing date of that adjustment, until 31 December 2010, the closing date ofthe new adjustment The 2010 set replaces the previously recommended 2006 CODATA set and may also be found

on the World Wide Web at physics.nist.gov/constants

Reference

1 Nakamura, K., K Hagiwara, K Hikasa, H Murayama, M Tanabashi, T Watari, C Amsler, M Antonelli, D M Asner,

H Baer, and e al, 2010, J Phys G 37, 075021.

TABLE I: An abbreviated list of the CODATA recommended values of the fundamental

constants of physics and chemistry based on the 2010 adjustment.

Relative std.

F Cabiati, Istituto Nazionale di Ricerca Metrologica, Italy

J Fischer, Physikalisch-Technische Bundesanstalt, Germany

J Flowers, National Physical Laboratory, United Kingdom

K Fujii, National Metrology Institute of Japan, Japan

S G Karshenboim, Pulkovo Observatory, Russian Federation

P J Mohr, National Institute of Standards and Technology, United States of America

D B Newell, National Institute of Standards and Technology, United States of America

F Nez, Laboratoire Kastler-Brossel, France

K Pachucki, University of Warsaw, Poland

T J Quinn, Bureau international des poids et mesures

B N Taylor, National Institute of Standards and Technology, United States of America

B M Wood, National Research Council, Canada

Z Zhang, National Institute of Metrology, China (People’s Republic of)

†Electronic address: mohr@nist.gov

‡Electronic address: barry.taylor@nist.gov

§Electronic address: dnewell@nist.gov

1-1

TABLE I: (Continued.)

Relative std.

Stefan-Boltzmann constant

Non-SI units accepted for use with the SI

1See Table IV for the conventional value adopted internationally for realizing representations of the volt using the Josephson effect

2See Table IV for the conventional value adopted internationally for realizing representations of the ohm using the quantum Hall effect

TABLE II: (Continued).

Relative std.

ATOMIC AND NUCLEAR

electron magnetic moment

electron to shielded proton magnetic

electron to shielded helion magnetic

3Value recommended by the Particle Data Group (Nakamura et al., 2010)

4Based on the ratio of the masses of the W and Z bosons mW/mZrecommended by the Particle Data Group (Nakamura et al., 2010) The valuefor sin2

Wthey recommend, which is based on a particular variant of the modified minimal subtraction (MS) scheme, is sin2ˆθW(MZ) = 0.231 16(13).

Relative std.

Stefan-Boltzmann constant

Non-SI units accepted for use with the SI

1See Table IV for the conventional value adopted internationally for realizing representations of the volt using the Josephson effect

2See Table IV for the conventional value adopted internationally for realizing representations of the ohm using the quantum Hall effect

Relative std.

ATOMIC AND NUCLEAR

electron magnetic moment

electron to shielded proton magnetic

electron to shielded helion magnetic

3Value recommended by the Particle Data Group (Nakamura et al., 2010)

4Based on the ratio of the masses of the W and Z bosons mW/mZrecommended by the Particle Data Group (Nakamura et al., 2010) The valuefor sin2

Wthey recommend, which is based on a particular variant of the modified minimal subtraction (MS) scheme, is sin2ˆθW(MZ) = 0.231 16(13).

TABLE II: (Continued).

Relative std.

muon magnetic moment anomaly

proton magnetic shielding correction

neutron to shielded proton magnetic

Relative std.

muon magnetic moment anomaly

5This and all other values involving mτare based on the value of mτ 2in MeV recommended by the Particle Data Group (Nakamura et al.,

2010)

Relative std.

proton magnetic shielding correction

neutron to shielded proton magnetic

TABLE II: (Continued).

shielded helion to proton magnetic

shielded helion to shielded proton magnetic

PHYSICOCHEMICAL

atomic mass constant

6The numerical value of F to be used in coulometric chemical measurements is 96 485.3321(43) [4.4 × 10−8] when the relevant current

is measured in terms of representations of the volt and ohm based on the Josephson and quantum Hall effects and the internationally adopted

conventional values of the Josephson and von Klitzing constants KJ−90and RK−90given in Table IV

TABLE II: (Continued).

Relative std.

Wien displacement law constants

b = λmaxT = c2/ 4.965 114 231 b 2.897 7721(26) × 10−3 m K 9.1 × 10−7

b�= νmax/ T = 2.821 439 372 c/c2 b� 5.878 9254(53) × 1010 Hz K−1 9.1 × 10−7

TABLE III: The variances, covariances, and correlation coefficients of the values of a selected group of constants based on the

2010 CODATA adjustment The numbers in bold above the main diagonal are 1016times the numerical values of the relative covariances; the numbers in bold on the main diagonal are 1016times the numerical values of the relative variances; and the

numbers in italics below the main diagonal are the correlation coefficients.1

r(x i ) = ur(x i , x i ): and the correlation coefficient is r(x i , x j ) = u(x i , x j )/[u(x i )u(x j)]

7The entropy of an ideal monoatomic gas of relative atomic mass Aris given by S = S0+3R ln Ar− R ln( p/p0) +5R ln(T/K).

shielded helion to proton magnetic

shielded helion to shielded proton magnetic

PHYSICOCHEMICAL

atomic mass constant

6The numerical value of F to be used in coulometric chemical measurements is 96 485.3321(43) [4.4 × 10−8] when the relevant current

is measured in terms of representations of the volt and ohm based on the Josephson and quantum Hall effects and the internationally adopted

conventional values of the Josephson and von Klitzing constants KJ−90and RK−90given in Table IV

Relative std.

Wien displacement law constants

b = λmaxT = c2/ 4.965 114 231 b 2.897 7721(26) × 10−3 m K 9.1 × 10−7

b�= νmax/ T = 2.821 439 372 c/c2 b� 5.878 9254(53) × 1010 Hz K−1 9.1 × 10−7

TABLE III: The variances, covariances, and correlation coefficients of the values of a selected group of constants based on the

2010 CODATA adjustment The numbers in bold above the main diagonal are 1016times the numerical values of the relative covariances; the numbers in bold on the main diagonal are 1016times the numerical values of the relative variances; and the

numbers in italics below the main diagonal are the correlation coefficients.1

r(x i ) = ur(x i , x i ): and the correlation coefficient is r(x i , x j ) = u(x i , x j )/[u(x i )u(x j)]

7The entropy of an ideal monoatomic gas of relative atomic mass Aris given by S = S0+3R ln Ar− R ln( p/p0) +5R ln(T/K).

TABLE IV: Internationally adopted values of various quantities.

Relative std.

TABLE V: Values of some x-ray-related quantities based on the 2010 CODATA adjustment of the values of the constants.

Relative std.

{220} lattice spacing of Si a/√8 d220 192.015 5714(32) × 10−12 m 1.6 × 10−8

imperfections, and is deduced from measurements on extremely pure and nearly perfect single crystals of Si by correcting for the

effects of impurities

TABLE VI: The values in SI units of some non-SI units based on the 2010 CODATA adjustment of the values of the constants.

Relative std.

Non-SI units accepted for use with the SI

Natural units (n.u.)

Atomic units (a.u.)

TABLE VII: The values of some energy equivalents derived from the relations E = mc2= hc/λ = hν = kT, and based on the 2010

CODATA adjustment of the values of the constants; 1 eV = (e/C) J, 1 u = mu= 121m(12C) = 10−3kg mol−1/NA, and

Eh= 2R∞hc = α2mec2is the Hartree energy (hartree).

TABLE IV: Internationally adopted values of various quantities.

Relative std.

TABLE V: Values of some x-ray-related quantities based on the 2010 CODATA adjustment of the values of the constants.

Relative std.

{220} lattice spacing of Si a/√8 d220 192.015 5714(32) × 10−12 m 1.6 × 10−8

imperfections, and is deduced from measurements on extremely pure and nearly perfect single crystals of Si by correcting for the

effects of impurities

TABLE VI: The values in SI units of some non-SI units based on the 2010 CODATA adjustment of the values of the constants.

Relative std.

Non-SI units accepted for use with the SI

Natural units (n.u.)

Atomic units (a.u.)

TABLE VII: The values of some energy equivalents derived from the relations E = mc2= hc/λ = hν = kT, and based on the 2010

CODATA adjustment of the values of the constants; 1 eV = (e/C) J, 1 u = mu= 121m(12C) = 10−3kg mol−1/NA, and

Eh= 2R∞hc = α2mec2is the Hartree energy (hartree).

TABLE VIII: The values of some energy equivalents derived from the relations E = mc2= hc/λ = hν = kT, and based on the

2010 CODATA adjustment of the values of the constants; 1 eV = (e/C) J, 1 u = mu= 121m(12C) = 10−3kg mol−1/NA, and

Eh= 2R∞hc = α2mec2is the Hartree energy (hartree).

(IUPAC) Commission on Isotopic Abundances and Atomic Weights

(Ref 1 and 5) Those changes affected the following 24 elements:

aluminum, arsenic, beryllium, bromine, cadmium, cesium, cobalt,

fluorine, germanium, gold, holmium, indium, magnesium,

manga-nese, mercury, molybdenum, niobium, phosphorus,

praseodymi-um, scandipraseodymi-um, selenipraseodymi-um, thoripraseodymi-um, thulipraseodymi-um, and yttrium

IUPAC made a significant policy change in 2009 (Ref 2 - 4)

Each atomic weight had previously been given as a single value

with an uncertainty that took into account both the measurement

uncertainty and the variation in isotopic abundance in samples of

the element from different terrestrial sources For a variety of

rea-sons (Ref 3) this fails to give complete information on the natural

variability in isotopic abundance of several elements Therefore,

the 2009 recommendations expressed the atomic weights of 10

el-ements as intervals rather than single numbers plus uncertainties

The symbol for these intervals is [a, b], where a is the lower bound

of values found in normal materials, and b the upper bound In

the new recommendations 2 additional elements, bromine and

magnesium, have been added to the list for which an interval is

given For the other elements in the table, a single recommended

Table 1 gives the 2013 atomic weights of the elements listed in alphabetical order by name Table 2 gives reference atomic weights for the 12 elements whose entries in Table 1 are intervals rather than single numbers These conventional values are suggested for use on samples of unspecified origin and for calculation of mo-lecular weights in tables intended to be broadly applicable They have been selected such that most or all natural terrestrial atomic-weight variation is covered in an interval of plus or minus one in the last digit It should be emphasized that the conventional values are not simply midpoints of the intervals, but rather represent the best judgment of the data evaluators

References

1 Wieser, M E et al , Pure Appl Chem 85, 1047, 2013

2 Wieser, M E , and Coplen, T D , Pure Appl Chem 83, 359, 2011

3 Coplen, T B , and Holden, N E , Chemistry International, Vol 33, No

2, p 10, 2011

4 Berglund, M , and Wieser, M E , Pure Appl Chem 83, 397, 2011

5 Chemistry International, Vol 35, No 6, p 17, 2013 <www ciaaw org>

TABLE 1 STANDARD ATOMIC WEIGHTS 2011

Element Symbol Number Atomic Atomic Weight Footnotes

Element Symbol Number Atomic Atomic Weight Footnotes

r Range in isotopic composition of normal terrestrial material prevents a more precise atomic weight being given; the tabulated value and uncertainty should be applicable

to any normal material

u Element has no stable isotopes See “Table of the Isotopes” in Sec 11 for individual isotopic masses However, four such elements (Bi, Th, Pa, and U) do have a tic terrestrial isotopic composition, and for these elements standard atomic weights are tabulated

characteris-TABLE 2 CONVENTIONAL ATOMIC WEIGHTS (2011)

Element Symbol Number Atomic Reference Atomic Weight a

unspeci-the natural abundance (in percent) of unspeci-the stable nuclides and a few

important radioactive nuclides The atomic masses were taken

from the AME 2012 evaluation of the Atomic Mass Data Center,

now located at the Institute of Modern Physics in Lanzhou, China

(Ref 1 and 2) The number in parentheses following the mass

val-ue is the uncertainty in the last digit(s) given The mass valval-ues for

elements with Z = 102 and higher were derived from a

combina-tion of experimental data and systematic trends

Natural abundance values were taken from the IUPAC Technical

Report “Atomic Weight of the Elements: Review 2000” (Ref 3);

these entries are also followed by uncertainties in the last digit(s)

of the stated values This uncertainty includes both the estimated

measurement uncertainty and the reported range of variation

in different terrestrial sources of the element (see Ref 3 for full

details and caveats regarding elements whose abundance is

vari-able) The absence of an entry in the Abundance column indicates

isotopic composition varies so widely that a meaningful natural abundance cannot be defined

Reference 1 contains mass data on over 3000 nuclides and scribes the evaluation procedure in detail Masses and other prop-erties of nuclides may also be found in Section 11, “Table of the Isotopes” (Ref 4)

de-References

1 Wang, M., Audi, G., Wapstra, A H., Kondev, F G., MacCormick, M.,

Xu, X., and Pfeiffer, B., Chin Phys C 36, 1603-2014, 2012.

2 <http//amdc.impcas.ac.cn>

3 de Laeter, J R., Böhlke, J K., De Bièvre, P., Hidaka, H., Peiser, H S.,

Rosman, K J R., and Taylor, P D P., Pure Appl Chem 75, 683, 2003.

4 Holden, N E., “Table of the Isotopes”, in Haynes, W M., Ed., CRC

Handbook of Chemistry and Physics, 95th Ed., CRC Press, Boca Raton,

Z Isotope Mass in u Abundance in %

Z Isotope Mass in u Abundance in %

William C Martin

The ground state electron configuration, ground level, and

ion-ization energy of the elements hydrogen through rutherfordium

are listed in this table The electron configurations of elements

heavier than neon are shortened by using rare-gas element

sym-bols in brackets to represent the corresponding electrons See the

references for details of the notation for Pa, U, and Np Ionization

energies to higher states (and more precise values of the first

ion-ization energy for certain elements) may be found in the table

“Ionization Energies of Atoms and Atomic Ions” in Section 10 of

this Handbook.

References

1 Martin, W C., Musgrove, A., Kotochigova, S., and Sansonetti, J E., NIST Physical Reference Data Web Site, <www.nist.gov/pml/data/ion_energy.cfm>, June 2013

2 Martin, W C., and Wiese, W L., “Atomic Spectroscopy”, in Atomic,

Molecular, & Optical Physics Handbook, ed by G.W.F Drake (AIP,

Woodbury, NY, 1996) Chapter 10, pp 135-153

Z Element Ground-state configuration Ground level energy (eV) Ionization

Z Element Ground-state configuration Ground level energy (eV) Ionization

A new temperature scale, the International Temperature Scale of

1990 (ITS-90), was officially adopted by the Comité International des

Poids et Mesures (CIPM), meeting 26—28 September 1989 at the

Bureau International des Poids et Mesures (BIPM) The ITS-90 was

recommended to the CIPM for its adoption following the

comple-tion of the final details of the new scale by the Comité Consultatif de

Thermométrie (CCT), meeting 12—14 September 1989 at the BIPM

in its 17th Session The ITS-90 became the official international

tem-perature scale on 1 January 1990 The ITS-90 supersedes the previous

scales, the International Practical Temperature Scale of 1968

(IPTS-68) and the 1976 Provisional 0.5 to 30 K Temperature Scale (EPT-76)

The ITS-90 (Ref 1, 2) extends upward from 0.65 K, and

tempera-tures on this scale are in much better agreement with

thermody-namic values than are those on the IPTS-68 and the EPT-76 The

new scale has subranges and alternative definitions in certain ranges

that greatly facilitate its use Furthermore, its continuity, precision,

and reproducibility throughout its ranges are much improved over

that of the previous scales The replacement of the thermocouple

with the platinum resistance thermometer at temperatures below

961.78 °C resulted in the biggest improvement in reproducibility

The ITS-90 is divided into four primary ranges:

1 Between 0.65 and 3.2 K, the ITS-90 is defined by the vapor

and 2.1768 K (the λ point) and between 2.1768 and 5.0 K

defined by the vapor pressure equations of the form:

i i

and C of the equations are given below.

2 Between 3.0 and 24.5561 K, the ITS-90 is defined in terms

The thermometer is calibrated at three temperatures — at the triple point of neon (24.5561 K), at the triple point of equilibrium hydrogen (13.8033 K), and at a temperature between 3.0 and 5.0 K, the value of which is determined by

3 Between 13.8033 K (–259.3467 °C) and 1234.93 K (961.78 °C), the ITS-90 is defined in terms of the specified fixed points given below, by resistance ratios of platinum resistance thermometers obtained by calibration at speci-fied sets of the fixed points, and by reference functions and

between the fixed points

4 Above 1234.93 K, the ITS-90 is defined in terms of Planck’s radiation law, using the freezing-point temperature of ei-ther silver, gold, or copper as the reference temperature.Since the adoption of ITS-90, the isotopic composition of the water and hydrogen whose fixed points appear in the table has been specified (Ref 3) A Provisional Low Temperature Scale (PLTS-2000) has been developed, covering the region from 0.9 mK to 1

e-H2 (or He) VP (or CVGT) ≈17 ≈ –256.15

e-H2 (or He) VP (or CVGT) ≈20.3 ≈ –252.85

4 He 1.25—2.1768 K

4 He 2.1768—5.0 K

c Previously, these were secondary fixed points.

1-19

This table gives temperature corrections from older scales to

the current International Temperature Scale of 1990 (see the

pre-ceding table for details on ITS-90) The first part of the table may

be used for converting Celsius temperatures in the range –180 to

4000 °C from IPTS-68 or IPTS-48 to ITS-90 Within the accuracy

of the corrections, the temperature in the first column may be

designed for use at lower temperatures to convert values expressed

in kelvins from EPT-76 or IPTS-68 to ITS-90

The references give analytical equations for expressing these lations Note that Reference 1 supersedes Reference 2 with respect

re-to corrections in the 630 re-to 1064 °C range

References

1 Burns, G W et al., in Temperature: Its Measurement and Control in

Science and Industry, Vol 6, Schooley, J F., Ed., American Institute of

Physics, New York, 1993

2 Goldberg, R N and Weir, R D., Pure and Appl Chem., 64, 1545, 1992.

The International System of Units, abbreviated as SI (from

the French name Le Système International d’Unités), was

es-tablished in 1960 by the 11th General Conference on Weights

and Measures (CGPM) as the modern metric system of

measure-ment The core of the SI is the seven base units for the physical

quantities length, mass, time, electric current, thermodynamic

temperature, amount of substance, and luminous intensity These

base units are:

The SI base units are defined as follows:

ampere: The ampere is that constant current which, if

main-tained in two straight parallel conductors of infinite length,

of negligible circular cross-section, and placed 1 meter

apart in vacuum, would produce between these

conduc-tors a force equal to 2∙10–7 newton per meter of length

candela: The candela is the luminous intensity, in a given

di-rection, of a source that emits monochromatic radiation of

frequency 540∙1012 hertz and that has a radiant intensity in

that direction of 1/683 watt per steradian

kelvin: The kelvin, unit of thermodynamic temperature, is the

fraction 1/273 16 of the thermodynamic temperature of

the triple point of water

kilogram: The kilogram is the unit of mass; it is equal to the

mass of the international prototype of the kilogram

meter: The meter is the length of the path travelled by light

in vacuum during a time interval of 1/299 792 458 of a

second

mole: The mole is the amount of substance of a system which

contains as many elementary entities as there are atoms in

0 012 kilogram of carbon 12 When the mole is used, the

elementary entities must be specified and may be atoms,

molecules, ions, electrons, other particles, or specified

groups of such particles

second: The second is the duration of 9 192 631 770 periods

of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium

133 atom

SI derived units

Derived units are units which may be expressed in terms of base units by means of the mathematical symbols of multiplication and division (and, in the case of °C, subtraction) Certain derived units have been given special names and symbols, and these special names and symbols may themselves be used in combination with those for base and other derived units to express the units of other quantities The next table lists some examples of derived units ex-pressed directly in terms of base units:

SI derived unit

concentration (of amount

(a) The symbol “1” is generally omitted in combination with a numerical value

For convenience, certain derived units, which are listed in the next table, have been given special names and symbols These names and symbols may themselves be used to express other de-rived units The special names and symbols are a compact form for the expression of units that are used frequently The final column shows how the SI units concerned may be expressed in terms of SI base units In this column, factors such as m0,kg0 , which are all equal to 1, are not shown explicitly

SI derived unit expressed in terms of

1-22

Physical quantity Name Symbol Other SI units SI base units

dose equivalent, ambient dose

equivalent, directional dose equivalent,

personal dose equivalent, organ equivalent dose

(a) The radian and steradian may be used with advantage in expressions for derived units to distinguish between quantities of different nature

but the same dimension Some examples of their use in forming derived units are given in the next table

(b) In practice, the symbols rad and sr are used where appropriate, but the derived unit “1” is generally omitted in combination with a

numerical value

(c) In photometry, the name steradian and the symbol sr are usually retained in expressions for units

(d) It is common practice to express a thermodynamic temperature, symbol T, in terms of its difference from the reference temperature T0 =

273 15 K The numerical value of a Celsius temperature t expressed in degrees Celsius is given by t/°C = T/K-273 15 The unit °C may be

used in combination with SI prefixes, e g , millidegree Celsius, m ° C Note that there should never be a space between the ° sign and the

letter C, and that the symbol for kelvin is K, not °K

The SI derived units with special names may be used in

com-binations to provide a convenient way to express more complex

physical quantities Examples are given in the next table:

SI derived unit

angular acceleration radian per second

heat flux density,

specific heat capacity,

2 ∙ s–2 ∙ K–1

thermal conductivity watt per meter

molar entropy, molar

In practice, with certain quantities preference is given to the use

of certain special unit names, or combinations of unit names, in

order to facilitate the distinction between different quantities ing the same dimension For example, the SI unit of frequency is designated the hertz, rather than the reciprocal second, and the SI unit of angular velocity is designated the radian per second rather than the reciprocal second (in this case retaining the word radian emphasizes that angular velocity is equal to 2π times the rotational frequency) Similarly the SI unit of moment of force is designated the newton meter rather than the joule

hav-In the field of ionizing radiation, the SI unit of activity is nated the becquerel rather than the reciprocal second, and the SI units of absorbed dose and dose equivalent the gray and sievert, re-spectively, rather than the joule per kilogram In the field of cataly-sis, the SI unit of catalytic activity is designated the katal rather than the mole per second The special names becquerel, gray, sievert, and katal were specifically introduced because of the dangers to human health which might arise from mistakes involving the units reciprocal second, joule per kilogram and mole per second

desig-Units for dimensionless quantities, quantities of dimension one

Certain quantities are defined as the ratios of two quantities of the same kind, and thus have a dimension which may be expressed

by the number one The unit of such quantities is necessarily a derived unit coherent with the other units of the SI and, since it

is formed as the ratio of two identical SI units, the unit also may

be expressed by the number one Thus the SI unit of all quantities having the dimensional product one is the number one Examples

of such quantities are refractive index, relative permeability, and friction factor Other quantities having the unit 1 include “char-acteristic numbers” like the Prandtl number and numbers which represent a count, such as a number of molecules, degeneracy (number of energy levels), and partition function in statistical thermodynamics All of these quantities are described as being di-mensionless, or of dimension one, and have the coherent SI unit

1 Their values are simply expressed as numbers and, in general, the unit 1 is not explicitly shown In a few cases, however, a spe-cial name is given to this unit, mainly to avoid confusion between some compound derived units This is the case for the radian, ste-radian and neper

SI prefixes

The following prefixes have been approved by the CGPM for

use with SI units Only one prefix may be used before a unit Thus

10–12 farad should be designated pF, not μμF

Among the base units of the International System, the unit of

mass is the only one for which the name, for historical reasons,

contains a prefix Names and symbols for decimal multiples and

submultiples of the unit of mass are formed by attaching prefix

names to the unit name “gram” and prefix symbols to the unit

sym-bol “g”

Example: 10–6 kg = 1 mg (1 milligram) but not 1 μkg

(1 microkilogram)

Units used with the SI

Many units that are not part of the SI are important and widely

used in everyday life The CGPM has adopted a classification of

non-SI units: (1) units accepted for use with the SI (such as the

traditional units of time and of angle); (2) units accepted for use

with the SI whose values are obtained experimentally; and (3)

oth-er units currently accepted for use with the SI to satisfy the needs

of special interests

(1) Non-SI units accepted for use with the International System

(a) The neper is used to express values of such logarithmic quantities as

field level, power level, sound pressure level, and logarithmic decrement

Natural logarithms are used to obtain the numerical values of quantities

expressed in nepers The neper is coherent with the SI, but is not yet

adopted by the CGPM as an SI unit In using the neper, it is important

to specify the quantity

(b) The bel is used to express values of such logarithmic quantities as field

level, power level, sound-pressure level, and attenuation Logarithms to

base ten are used to obtain the numerical values of quantities expressed

in bels The submultiple decibel, dB, is commonly used

(2) Non-SI units accepted for use with the International system, whose values in SI units are obtained experimentally

(b) The electronvolt is the kinetic energy acquired by an electron in passing through a potential difference of 1 V in vacuum

(c) The dalton and unified atomic mass unit are alternative names for the same unit, equal to 1/12 of the mass of an unbound atom of the nuclide 12 C, at rest and in its ground state The dalton may be combined with SI prefixes to express the masses of large molecules in kilodalton, kDa, or megadalton, MDa

(d) The mean Earth-Sun distance is approximately equal to the astronomical unit

(3) Other non-SI units currently accepted for use with the

International System

Other non-SI units

The SI does not encourage the use of cgs units, but these are frequently found in old scientific texts The following table gives the relation of some common cgs units to SI units

Name Symbol Value in SI units

Note: The symbol ≙ should be read as “corresponds to”;

these units cannot strictly be equated because of the different dimensions of the electromagnetic cgs and the SI

Examples of other non-SI units found in the older literature and their relation to the SI are given below Use of these units in cur-rent texts is discouraged

(a) Several types of calorie have been used; the value given here is the so-called

“thermochemical calorie”

Prefixes for binary multiples

In December 1998, the International Electrotechnical

Commission (IEC), the leading international organization for

worldwide standardization in electrotechnology, approved as an

IEC International Standard names and symbols for prefixes for

binary multiples for use in the fields of data processing and data

transmission The prefixes are as follows:

Prefixes for binary multiples

Examples and comparisons with SI prefixes

of ten As can be seen from the above table, the name of each new prefix is derived from the name of the corresponding SI prefix by retaining the first two letters of the name of the SI prefix and add-ing the letters “bi,” which recalls the word “binary ” Similarly, the symbol of each new prefix is derived from the symbol of the cor-responding SI prefix by adding the letter “i,” which again recalls the word “binary ” (For consistency with the other prefixes for binary multiples, the symbol Ki is used for 210 rather than ki )

References

1 Taylor, B N , and Thompson, A , The International System of Unit (SI), NIST Special Publication 330, National Institute of Standards

and Technology, Gaithersburg, MD, 2008

2 Bureau International des Poids et Mesures, Le Système International

d’Unités (SI), 8th French and English Edition, BIPM, Sèvres, France,

2006

3 Thompson, A , and Taylor, B N , Guide for the Use of the International

System of Unit (SI), NIST Special Publication 811, National Institute

of Standards and Technology, Gaithersburg, MD, 2008

4 NIST Physical Reference Data web site, http://physics nist gov/cuu/Units/index html, October 2004

5 Amendment  2 to IEC International Standard IEC  60027-2,

1999-01, Letter symbols to be used in electrical technology – Part 2: Telecommunications and electronics

6 IEC 60027-2, Second edition, 2000-11, Letter symbols to be used in electrical technology - Part 2: Telecommunications and electronics

7 Barrow, B , “A Lesson in Megabytes,” IEEE Stand Bearer, January

1997, p  5

The following table gives conversion factors from various

units of measure to SI units It is reproduced from NIST Special

Publication 811, Guide for the Use of the International System of

Units (SI) The table gives the factor by which a quantity expressed

in a non-SI unit should be multiplied in order to calculate its value

in the SI The SI values are expressed in terms of the base,

supple-mentary, and derived units of SI in order to provide a coherent

presentation of the conversion factors and facilitate computations

(see the table “International System of Units” in this section) If

desired, powers of ten can be avoided by using SI prefixes and

shifting the decimal point if necessary

Conversion from a non-SI unit to a different non-SI unit may be

carried out by using this table in two stages, e g ,

1 calth = 4 184 J

1 BtuIT = 1 055056 E+03 JThus,

1 BtuIT = (1 055056 E+03 ÷ 4 184) calth = 252 164 calth

Conversion factors are presented for ready adaptation to

com-puter readout and electronic data transmission The factors are

written as a number equal to or greater than one and less than ten

with six or fewer decimal places This number is followed by the

letter E (for exponent), a plus or a minus sign, and two digits that

indicate the power of 10 by which the number must be multiplied

to obtain the correct value For example:

3 523 907 E-02 is 3 523 907 × 10–2

or

0 035 239 07Similarly:

1 If the digits to be discarded begin with a digit less than 5, the digit preceding the first discarded digit is not changed Example: 6 974 951 5 rounded to 3 digits is 6 97

2 If the digits to be discarded begin with a digit greater than

5, the digit preceding the first discarded digit is increased

by one Example: 6 974 951 5 rounded to 4 digits is 6 975

3 If the digits to be discarded begin with a 5 and at least one

of the following digits is greater than 0, the digit preceding the 5 is increased by 1

Example: 6 974 851 rounded to 5 digits is 6 974 9

4 If the digits to be discarded begin with a 5 and all of the lowing digits are 0, the digit preceding the 5 is unchanged

fol-if it is even and increased by one fol-if it is odd (Note that this means that the final digit is always even )

Examples:

6 974 951 5 rounded to 7 digits is 6 974 952

6 974 950 5 rounded to 7 digits is 6 974 950

Reference

Thompson, A , and Taylor, B N , Guide for the Use of the International

System of Units (SI), NIST Special Publication 811, 2008 Edition,

Superintendent of Documents, U S Government Printing Office, Washington, D C 20402, 2008

Factors in boldface are exact

abampere ampere (A) 1.0 E+01 abcoulomb coulomb (C) 1.0 E+01 abfarad farad (F) 1.0 E+09 abhenry henry (H) 1.0 E–09 abmho siemens (S) 1.0 E+09 abohm ohm (Ω) 1.0 E–09 abvolt volt (V) 1.0 E–08

acceleration of free fall, standard (gn) meter per second squared (m/s2) 9.806 65 E+00

acre (based on U S survey foot)a square meter (m2) 4 046 873 E+03acre foot (based on U S survey foot)a cubic meter (m3) 1 233 489 E+03

ampere hour (A ∙ h) coulomb (C) 3.6 E+03 ångström (Å) meter (m) 1.0 E–10 ångström (Å) nanometer (nm) 1.0 E–01

apostilb (asb) candela per meter squared (cd/m2) 3 183 098 E–01are (a) square meter (m2) 1.0 E+02 astronomical unit (au) meter (m) 1.495 978 70700 E+11 atmosphere, standard (atm) pascal (Pa) 1.013 25 E+05 atmosphere, standard (atm) kilopascal (kPa) 1.013 25 E+02

atmosphere, technical (at)b pascal (Pa) 9.806 65 E+04

atmosphere, technical (at)b kilopascal (kPa) 9.806 65 E+01

a The U S survey foot equals (1200/3937) m 1 international foot = 0 999998 survey foot

b One technical atmosphere equals one kilogram-force per square centimeter (1 at = 1 kgf/cm 2 )

1-27

bar (bar) kilopascal (kPa) 1.0 E+02

barn (b) square meter (m2) 1.0 E–28

barrel [for petroleum, 42 gallons (U S )](bbl) cubic meter (m3) 1 589 873 E–01barrel [for petroleum, 42 gallons (U S )](bbl) liter (L) 1 589 873 E+02biot (Bi) ampere (A) 1.0 E+01

British thermal unitIT (BtuIT)c joule (J) 1 055 056 E+03British thermal unitth (Btuth)c joule (J) 1 054 350 E+03British thermal unit (mean) (Btu) joule (J) 1 055 87 E+03British thermal unit (39 ºF) (Btu) joule (J) 1 059 67 E+03British thermal unit (59 ºF) (Btu) joule (J) 1 054 80 E+03British thermal unit (60 ºF) (Btu) joule (J) 1 054 68 E+03British thermal unitIT foot per hour square foot degree Fahrenheit

[BtuIT ∙ ft/(h ∙ ft2∙ ºF)] watt per meter kelvin [W/(m ∙ K)] 1 730 735 E+00British thermal unitth foot per hour square foot degree Fahrenheit

[Btuth ∙ ft/(h ∙ ft2∙ ºF)] watt per meter kelvin [W/(m ∙ K)] 1 729 577 E+00British thermal unitIT inch per hour square foot degree Fahrenheit

[BtuIT ∙ in/(h ∙ ft2∙ ºF)] watt per meter kelvin [W/(m ∙ K)] 1 442 279 E–01British thermal unitth inch per hour square foot degree Fahrenheit

[Btuth ∙ in/(h ∙ ft2∙ ºF)] watt per meter kelvin [W/(m ∙ K)] 1 441 314 E–01British thermal unitIT inch per second square foot degree Fahrenheit

[BtuIT ∙ in/(s ∙ ft2∙ ºF)] watt per meter kelvin [W/(m ∙ K)] 5 192 204 E+02British thermal unitth inch per second square foot degree Fahrenheit

[Btuth ∙ in/(s ∙ ft2∙ ºF)] watt per meter kelvin [W/(m ∙ K)] 5 188 732 E+02British thermal unitIT per cubic foot

(BtuIT/ft3) joule per cubic meter (J/m3) 3 725 895 E+04British thermal unitth per cubic foot

(Btuth/ft3) joule per cubic meter (J/m3) 3 723 403 E+04British thermal unitIT per degree Fahrenheit

(BtuIT/ºF) joule per kelvin (J/k) 1 899 101 E+03British thermal unitth per degree Fahrenheit

(Btuth/ºF) joule per kelvin (J/k) 1 897 830 E+03British thermal unitIT per degree Rankine

(BtuIT/ºR) joule per kelvin (J/k) 1 899 101 E+03British thermal unitth per degree Rankine

(Btuth/ºR) joule per kelvin (J/k) 1 897 830 E+03British thermal unitIT per hour (BtuIT/h) watt (W) 2 930 711 E–01British thermal unitth per hour (Btuth/h) watt (W) 2 928 751 E–01British thermal unitIT per hour square foot degree Fahrenheit

[BtuIT/(h ∙ ft2∙ ºF)] watt per square meter kelvin

[W/(m2 ∙ K)] 5 678 263 E+00British thermal unitth per hour square foot degree Fahrenheit

[Btuth/(h ∙ ft2 ∙ ºF)] watt per square meter kelvin

[W/(m2∙ K)] 5 674 466 E+00British thermal unitth per minute (Btuth/min) watt (W) 1 757 250 E+01British thermal unitIT per pound (BtuIT/lb) joule per kilogram (J/kg) 2.326 E+03

British thermal unitth per pound (Btuth/lb) joule per kilogram (J/kg) 2 324 444 E+03British thermal unitIT per pound degree Fahrenheit

[BtuIT/(lb ∙ ºF)] joule per kilogram kelvin (J/(kg ∙ K)] 4.1868 E+03

British thermal unitth per pound degree Fahrenheit

[Btuth/(lb ∙ ºF)] joule per kilogram kelvin [J/(kg ∙ K)] 4.184 E+03

British thermal unitIT per pound degree Rankine

[BtuIT/(lb ∙ ºR)] joule per kilogram kelvin [J/(kg ∙ K)] 4.1868 E+03

British thermal unitth per pound degree Rankine

[Btuth/(lb ∙ ºR)] joule per kilogram kelvin [J/(kg ∙ K)] 4.184 E+03

British thermal unitIT per second (BtuIT/s) watt (W) 1 055 056 E+03British thermal unitth per second (Btuth/s) watt (W) 1 054 350 E+03

c The Fifth International Conference on the Properties of Steam (London, July 1956) defined the International Table calorie as 4 1868 J Therefore the exact conversion factor for the International Table Btu is 1 055 055 852 62 kJ Note that the notation for the International Table used in this listing is subscript “IT” Similarily, the notation for thermochemical is subscript “th ” Further, the thermochemical Btu, Btuth, is based on the thermochemical calorie, calth, where calth = 4 184 J exactly

To convert from to Multiply by

British thermal unitIT per second square foot degree Fahrenheit

[BtuIT/(s ∙ ft2 ∙ ºF)] watt per square meter kelvin

[W/(m2 ∙ K)] 2 044 175 E+04British thermal unitth per second square foot degree Fahrenheit

[Btuth/(s ∙ ft2 ∙ ºF)] watt per square meter kelvin

[W/(m2 ∙ K)] 2 042 808 E+04British thermal unitIT per square foot

(BtuIT/ft2) joule per square meter (J/m2) 1 135 653 E+04British thermal unitth per square foot

(Btuth/ft2) joule per square meter (J/m2) 1 134 893 E+04British thermal unitIT per square foot hour

[(BtuIT/(ft2 ∙ h)] watt per square meter (W/m2) 3 154 591 E+00British thermal unitth per square foot hour

[Btuth/(ft2 ∙ h)] watt per square meter (W/m2) 3 152 481 E+00British thermal unitth per square foot minute

[Btuth/(ft2 ∙ min)] watt per square meter (W/m2) 1 891 489 E+02British thermal unitIT per square foot second

[(BtuIT/(ft2 ∙ s)] watt per square meter (W/m2) 1 135 653 E+04British thermal unitth per square foot second

[Btuth/(ft2 ∙ s)] watt per square meter (W/m2) 1 134 893 E+04British thermal unitth per square inch second

[Btuth/(in2 ∙ s)] watt per square meter (W/m2) 1 634 246 E+06bushel (U S ) (bu) cubic meter (m3) 3 523 907 E–02bushel (U S ) (bu) liter (L) 3 523 907 E+01calorieIT (calIT)c joule (J) 4.1868 E+00

calorieth (calth)c joule (J) 4.184 E+00

calorie (cal) (mean) joule (J) 4 190 02 E+00calorie (15 ºC) (cal15) joule (J) 4 185 80 E+00calorie (20 ºC) (cal20) joule (J) 4 181 90 E+00calorieIT, kilogram (nutrition)d joule (J) 4.1868 E+03

calorieth, kilogram (nutrition)d joule (J) 4.184 E+03

calorie (mean), kilogram (nutrition)d joule (J) 4 190 02 E+03calorieth per centimeter second degree Celsius

[calth/(cm ∙ s ∙ ºC)] watt per meter kelvin [W/(m ∙ K)] 4.184 E+02

calorieIT per gram (calIT/g) joule per kilogram (J/kg) 4.1868 E+03

calorieth per gram (calth/g) joule per kilogram (J/kg) 4.184 E+03

calorieIT per gram degree Celsius

[calIT/(g ∙ ºC)] joule per kilogram kelvin [J/(kg ∙ K)] 4.1868 E+03

calorieth per gram degree Celsius

[calth/(g ∙ ºC)] joule per kilogram kelvin [J/(kg ∙ K)] 4.184 E+03

calorieIT per gram kelvin [calIT/(g ∙ K)] joule per kilogram kelvin [J/(kg ∙ K)] 4.1868 E+03

calorieth per gram kelvin [calth/(g ∙ K)] joule per kilogram kelvin [J/(kg ∙ K)] 4.184 E+03

calorieth per minute (calth/min) watt (W) 6 973 333 E–02calorieth per second (calth/s) watt (W) 4.184 E+00

calorieth per square centimeter (calth/cm2) joule per square meter (J/m2) 4.184 E+04

calorieth per square centimeter minute

[calth/(cm2∙ min)] watt per square meter (W/m2) 6 973 333 E+02calorieth per square centimeter second

[calth/(cm2∙ s)] watt per square meter (W/m2) 4.184 E+04

candela per square inch (cd/in2) candela per square meter (cd/m2) 1 550 003 E+03carat, metric kilogram (kg) 2.0 E–04

carat, metric gram (g) 2.0 E–01

centimeter of mercury (0 ºC)e pascal (Pa) 1 333 22 E+03centimeter of mercury (0 ºC)e kilopascal (kPa) 1 333 22 E+00centimeter of mercury, conventional (cmHg)e pascal (Pa) 1 333 224 E+03

d The kilogram calorie or “large calorie” is an obsolete term used for the kilocalorie, which is the calorie used to express the energy content of foods However, in practice, the prefix “kilo” is usually omitted

e Conversion factors for mercury manometer pressure units are calculated using the standard value for the acceleration of gravity and the density of mercury at the stated temperature Additional digits are not justified because the definitions of the units do not take into account the compressibility of mercury or the change in density caused

by the revised practical temperature scale, ITS-90 Similar comments also apply to water manometer pressure units Conversion factors for conventional mercury and water manometer pressure units are based on ISO 31-3