Historic, Archive Document Do not assume content reflects current scientific knowledge, policies, or practices. D_A DJIMAfiS NATIONAL BUREAU OF STANDARDS REPORT 6484 Preliminary Report on the Thermodynamic Properties of Lithium, Beryllium, Magnesium, Aluminum and Their Compounds With Hydrogen, Oxygen, Nitrogen, Fluorine, and Chlorine (Supplement to NBS Report 6297) July 1, 1959 U. S. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS THE NATIONAL BUREAU OF STANDARDS Functions and Activities The functions of the National Bureau of Standards are set forth in the Act of Congress, March 3, 1901, as amended by Congress in Public Law 619, 1950. These include the development and maintenance of the national standards of measurement and the provision of means and methods for making measurements consistent with these standards; the determination of physical constants and properties of materials; the development of methods and instruments for testing materials, devices, and structures; advisory services to government agencies on scientific and technical problems; in- vention and development of devices to serve special needs of the Government; and the development of standard practices, codes, and specifications. The work includes basic and applied research, development, engineering, instrumentation, testing, evaluation, calibration services, and various consultation and information services. Research projects are also performed for other government agencies when the work relates to and supplements the basic program of the Bureau or when the Bureau’s unique competence is required. The scope of activities is suggested by the listing of divisions and sections on the inside of the back cover. Publications The results of the Bureau’s work take the form of either actual equipment and devices or pub- lished papers. These papers appear either in the Bureau’s own series of publications or in the journals of professional and scientific societies. The Bureau itself publishes three periodicals available from the Government Printing Office: The Journal of Research, pubhshed in four separate sections, presejnts complete scientific and technical papers; the Technical News Bulletin presents summary and preliminary reports on work in progress; and Basic Radio Propagation Predictions provides data for determining the best frequencies to use for radio communications throughout the world. There are also five series of nonperiodical publications: Monographs, Applied Mathematics Series, Handbooks, Miscellaneous Pubhcations, and Technical Notes. Information on the Bureau’s publications can be found in NBS Circular 460, Publications of tbe National Bureau of Standards ($1.25) and its Supplement ($1.50), availably from the Superintendent of Documents, Government Printing Office, Washington 25, D.C. NATIONAL BUREAU OF STANDARDS REPORT NBS PROJECT NBS REPORT 0302-11-03419 July 1, 1959 6484 0509-11-05513 0903-11-19430 0305-11-03496 Preliminary Report on the Thermodynamic Properties of Lithium, Beryllium, Magnesium, Aluminum and Their Compounds With Hydrogen, Oxygen, Nitrogen, Fluorine, and Chlorine (Supplement to NBS Report 6297) Second Technical Summary Report to the Advanced Research Projects Agency on the Thermodynamic Properties of Light-Element Compounds Reference: ARP A Order No. 20-59 IMPORTANT NOTICE NATIONAL BUREAU OF STAI rogress accounting doc- uments intended for use within Approved for public release by the is formally published it is subjected to additionoi evo director of the National Institute of cation, reprinting, repro- duction, or open-literature lis is not authorized unless Standards and Technology (NIST) , permission is obtained in writi eau of Standards, Wash- ington 25, D.C. Such permissi OctObeC 9, 2015 gency for which the Re- port has been specificallyprepa. j| copies for its own use. <NBS> U. S. DEPARTMENT OF COMMERCE NATIONAL DUREAU OF STANDARDS L ^ \ ' ’' ' ' '-®'w ...f :A%k'~i‘%' . \r\ • I .' ; V ' • ' ,.-' ' f]J?>ff^':';v^-;:H,v',.: . f '‘\^^’J-"':' ''• '* '.' ' ' • V.;>^^YvV 'J 'S ^*Tt/ i r iV/- f' ^ k'rf ii^ *y^‘ "'ifc 'A' WsSl.'«ttlfil.«J»-. .! .iS .'' f4;*.'^|j|i^A.‘' •tw'if'-"'--^''*^ y- - v'*.- »v,* ' i. '^k\ " ; ; /V: .(,. V - ,'- i »’. 'V'E V -^f & .*' '}' * . .„ ...... iiliKAi’A'* ••{;> ‘y^y. ’ /yy* '•( •'! > . f ,'( »i,i- 'i.“l<4'.»t -..jit.vo:. s.-ms i *' *- Ilf V... .1 » i-M'-v ' ..'1 vtW.; 'yW^v.^v. /rt . (. ' . ^ift : .. '. i» (IP V>i>' Sif-'. j ;-^W i'i ' V.'' “ A *n<->m< -' •" *f»*'.!«.tlbH ,,'.• ...-.•.'0 .I’tl '^t' ^’X;' I' (»,•.! Jrt^' *’'* ''•' '' I ' -:-ftiH>:> ff4'< .,' V V/* I y^'' .t4<fit.'ii>/|j|i^Vi,>»iy^.v-.'.f '-. y ' *'' ,, j,^i^iji<*»y, , '‘’*‘ V V.",V‘ \?f iil .-M v.'-« ... ^ . V.... yp . ‘ "-y ' ;«?k,;.'.J PP 'y - ‘,ii . ,„ '"•' , ::V' vi'>' :y\y>>':y4 yy ' :' ' 'y^ ': .y' ^ , • • ' . .. ppm .yp .y ...n ur.^'JSj.. W» .(4a ‘ " '^'^ ' '.' . , ii^ii •j,? »Vi.<t',*' . "f .;,* '!t ' ’ ^ «(.:', ,. ;'., : » ' ' 'f " .'"V. '.'’'W'' 'i ... ^. ,i/v‘ . PREFACE The National Bureau of Standards is undertaking an experimental and theoretical investigation of the t he miodynamic properties of light-element compounds. This research program presently comprises the chemical elements lithium, beryllium, magnesium, and aluminum, free and in combination with hydrogen, oxygen, nitrogen, fluorine, and/or chlorine. It has as its objective the securing of the basic information which is necessary to determine, with an accuracy of one per cent where possible, the energies and equilibrium propor- tions of these substances in the solid, liquid, and gaseous states in the temperature range from 0° to 6000°K and the pressure range from 0 to 100 atmospheres. The first year's program at NBS involves nine groups — namely, those in fluorine calorimetry, low-temperatue calorimetry, high-tem- perature calorimetry, statistical thermodynamics, high-temperature high-pressure phenomena, spectra, chemical preparation, thermochem- istry, and thermodynamics of refractory substances. This program is a part of a broader program at the National Bureau of Standards on properties of materials at high temperatures now required in many technical and scientific fields. The present report is divided into two parts. Part A summarizes the present status of the research program of each of the above nine groups, in terms of the accomplishments during the first nine months of the program and the plans for future work during the next fifteen months. The tentative nature of these future plans should be empha- sized. Although it is likely that most of the various experimental approaches will continue as outlined, with perhaps some shifts of emphasis, there may be major changes in and additions to the actual substances on which work will be done, owing to subsequent reevalua- tions of where data are most urgently needed. As our program pro- gresses, some modifications in its plans can be expected at inter- vals of six months or so. We feel that insofar as different labora- tories in this field indicate their tentative plans, the areas where specific data will be forthcoming can be better predict*^ and all laboratories can better mesh their efforts. Part B of the report is a revision and extension of our earlier report (NBS Report 6297) issued under date of last January 1. As 1 the table of contents suggests, some of the properties treated in that report have been modified in the light of more recently pub- lished data, whereas the treatment of other properties has been considerably expanded. This part of the present report also de- scribes in considerable detail some of the experimental apparatus being developed at the Bureau. The thermodynamic tables contained in this and in earlier re- ports will be revised periodically as new information becomes avail- able. Since many deficiencies in the available data exist, current tables are necessarily tentative. The reader sho\ild also note the paragraph on the title page of this report concerning NBS editorial policies. Charles W. Beckett, Chief Thermodynamics Section Heat Division 11 ABSTRACT A second comprehensive report is presented on an extensive experimental and theoretical investigation, at the National Bureau of Standards, of the thermodynamic properties of light-element compounds. This supplements and brings up-to-date the first report (dated January 1, 1959) ? with further data analysis and in addition a summary for each working group of research accomplishments and tentative plans for future work. Published data on heats of formation have been further reviewed, and values have been selected also for light-metal nitrides and carbides. The available low—temperature enthalpy data on solids and liquids have been carefully analyzed and joined smoothly to the corresponding high-temperature data. Equilibrium data for the vaporization of AI2O3, AIF3, LiF, and other light-metal fluorides and chlorides are examined critically for thermody- namic consistency. Molecular constants of some aluminum-oxygen molecules are estimated from semiempirical rules. High-speed computer programs were written for solids, liquids, and gases (including polyatomic molecules), and tables of thermodynamic functions are given for almost 30 solid and liquid substances and for 45 gas species. Experimental measurements, methods selected, and design and construc- tion of apparatus are described in some detail. Attempts were made to prepare the hydrides of beryllium and aluminum, in preparation for measur- ing their heats of formation and other properties. Preliminary measurements were made of the vapor pressures of a compound between aluminum