NATIONAL BUREAU OF STANDARDS REPORT 7437 Preliminary Report on the Thermodynamic Properties of Selected Light-Element and Some Related Compounds (Supplement to NBS Reports 6297, 6484, 6645/ 6928/ 7093/ and 7192) 1 January 1962 U. S. DEPARTMENT OF COMMERCE NATIONAL DUREAU 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 na- tional 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 agen- cies on scientific and technical problems; invention 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 research are published either in the Bureau’s own series of publications or in the journals of professional and scientific societies. The Bureau itself publishes three periodicals avail- able from the Government Printing Office: The Journal of Research, published in four separate sections, presents complete scientific and technical papers; the Technical News Bulletin presents summary and pre- liminary 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 non- periodical publications: Monographs, Applied Mathematics Series, Handbooks, Miscellaneous Publications, and Technical Notes. A complete listing of the Bureau’s publications can be found in National Bureau of Standards Circular 460, Publications of the National Bureau of Standards, 1901 to June 1947 ($1,25), and the Supplement to Na- tional Bureau of Standards Circular 460, July 1947 to June 1957 ($1.50), and Miscellaneous Publication 240, July 1957 to June 1960 (Includes Titles of Papers Published in Outside Journals 1950 to 1959) ($2.25); avail- able from the Superintendent of Documents, Government Printing Office, Washington 25, D. C. NATIONAL BUREAU OF STANDARDS REPORT NBS PROJECT NBS REPORT 0300-11-03419 1 January 1962 7437 0302-11-03426 0307-11-03471 0501-11-05496 0903-11-09430 1501-11-15513 1504-11-15491 Preliminary Report on the Thermodynamic Properties of Selected Light-Element and Some Related Compounds (Supplement to NBS Reports 6297, 6484, 6645, 6928, 7093, and 7192) Seventh Technical Summary Report to the Advanced Research Projects Agency on the Thermodynamic Properties of Light-Element Compounds Reference: ARPA Order No. 20-62 IMPORTANT NOTICE NATIONAL BUREAU OF STANF ccounting documents intended for use within the Government. Bef Approved for public release by the iected to additional evaluation and review. For this reason, the pu director of the National Institute of ing of this Report, either in whole or in part, is not authorized fice of the Director, National Standards and Technology (NIST) Bureau of Standards, Washington 2 Government agency for which the Report has been specifically prei on October 9, 2015 s for its own use. U. S. DEPARTMENT OF COMMERCE NATIONAL eUREAU OF STANDARDS ABSTRACT This is the seventh semi-annual report on the current experimental, theoretical, and evaluative program, at the National Bureau of Standards, on the thermodynamic properties of selected light-element compounds of primary interest in high-temperature research. In this connection the chemical elements principally involved are H, Li, Be, B, C, N, 0, F, At, Cl, and Zr, with more secondary interest in the compounds of Mg, Si, K, Ti, Br, I, W, Hg, and Pb. The emphasis in the NBS work has been on the simpler compounds of these elements. This report includes some recent NBS measurements under the program: The heat of formation of nitronium perchlorate, and the high-temperature heat capacity of aluminum carbide. As discussed in the report, precise measurements are essentially completed on the heat of combustion of aluminum in fluorine and on the low-temperature heat capacities and absolute entropies of LiH, and LiAlH^; however, these data are not yet presented, pending the resolution of small discrepancies needed to put the results on a final basis. Tables of thermodynamic functions (H H and are given for four gases omitted from earlier reports 2 > 02> , electron gas), and, on the basis of improved data, for the condensed phases of two substances (BeF2 and At^C^) . A contribution from those areas in which elaborate apparatus development is still progressing is a description in the report of a new fast-opening large-aperture shutter for high-speed photography. This development will be important in the study of combustions at very high temperatures and pressures. Also included are several up-to-date literature surveys in the field. One describes recent additions to the literature on the chemistry of numerous light-element compounds. A second describes alloys and inter- metallic compounds of aluminum and beryllium with titajaium and zirconium; while a third survey covers low-temperature heat capacities aud entropies of various substances, particularly the oxides of eight light elements. The fourth report is a comprehensive and critical assembly of the avail- able values for the heats of formation of a large number of compounds. !a/ Charles W. Beckett Assistant Division Chief for Thermodynamics Heat Division 1 TABLE OF CONTENTS Page Abstract i PART A. RECENT EXPERIMENTAL RESULTS AT THE NATIONAL BUREAU OF STANDARDS 1 Chap. Al. HEAT OF NEUTRALIZATION AND FORMATION OF NITRONIUM PERCHLORATE (by A. A. Gilliland) 3 1. Introduction 3 2. Constants and Conversion Factors .... 3 3. Materials 3 4. Apparatus and Procedure 3 5. Results and Calculations ........ 4 6 . Discussion 5 7. References 6 Table 1: Electrical Calibrations of the NOp CtO/ System ... 7 Table 2; Electrical Calibration on KN03/KCt04 System .... 8 Table 3' Results of the Experiments on the Hydrolysis of N02Ct04 . 9 Table U' Results of the Experiments on the Solution of KNO3 and KCt04 10 Chap. A2. FLUORINE-BOMB CALORIMETRY — A SUi'diARY OF WORK TO DATE (by George T. Armstrong, E. S. Domalski, and K. L. Churn ey) . 11 References 12 Chap. A3. ALUMINUM CARBIDE; HIGH-TEMPERATURE THERMODYNAMIC FUNCTIONS BASED ON RECENT MEASUREMENTS OF HEAT CAPACITY AT THE NATIONAL BUREAU OF STANDARDS (by Andrew C. Victor, Willis R. Thurber, and Thomas B. Douglas) 13 Table 1: Spectrochemical Analysis of Sample of 14 Table 2: Chemical Analysis of of At Sample 4C3 15 Table 3 ' Enthalpy Measurements on Aluminum Carbide 17 References 18 iii , TABLE OF CONTENTS (continued) Page Chap. A4. LOW-TEMPERATURE CALORIMETRY (by George T. Furukaua) 19 Chap. A5. A FAST-OPENING, LARGE- APERTURE SHUTTER FOR HIGH-SPEED PHOTOGRAPHY (by E. C. Cassidy and D. H. Tsai) ... 21 Abstract 21 Introduction 21 Experiments 23 Results and Discussion 24 Optimum Energy Input 26 Effect of Circuit Parameters 27 Effect of Size of the Foil ...... 30 Captions for Illustrations 32 Fig. 1: Experimental Setup with a Looped-Foil Shutter 33 Fig. 2: A Single Foil Shutter before Discharge (a) after Discharge (b) 34 Fig. 3 1 Opening Action of a Looped Foil Shutter 35 Fig. 4t Width of Opening versus Time of a Looped Foil Shutter . 36 PART B. RECENT LITERATURE SURVEYS 37 Chap. Bl. RECENT ADDITIONS TO THE LITERATURE ON THE CHEMISTRY OF THE LIGHT ELEMENTS (by Leslie A. Krleger and George T. Armstrong) 39 A. Aluminum Compounds 39 B. Boron Compounds 42 C. Beryllium Compounds 46 D. Lithium Compounds 49 E. Magnesium Compounds 51 F. Sodium Compounds 52 G. Titanium Compounds 54 H. Zirconium Compounds 56 I. Fluorine 58 J. Carbon 58 R. Chlorine . 58 L. Oxygen 58 M. Hydrogen 59 N. Nitrogen 60 IV * TifflLE OF CONTENTS (continued) Page Chap. B2. ALLOYS AND INTERSTITIAL COMPOUNDS OF ALUMINUM AND BERYLLIUM WITH TITANIUM AND ZIRCONIUM (by Thomas ¥. Means) 6l Aluminum- Zirconium system 6l Beryllium-Titanium system 6l Percent increase in volume of alloy or intermetallic as compared to elements . 62 References 62 Chap. B3. LITERATURE SURVEY ON LOW-TEMPERATURE HEAT CAPACITY AND ENTROPY AT 298.15°K OF BINARY METAL OXIDE COMPOUNDS OF Li, Be, Mg, At, Si, K, Ti, AND Zr AND OF ELEMENTAL Si AND K AND SOME OF THEIR COMPOUNDS (by George T. Furukawa) 63 Introduction 63 * Li 2Si Li20*3Si025 BepSiO^; Mg SiO^ . 20 02 > 2 64 At MgSi03 ; 2Si05 65 K O K O L Mg T 10 ... 66 2 *23102; 2 45102 ; 121103 ; 2 ^ ^ MgTi03 ; MgTi205 ; 4 21103 ; ZrSiO^ 67 MgWO^; Si; Si02 68 K; KO2 69 KF; KCt KHF2 ; 70 KBr; KI 71 Table 1: Binary Metal Oxide Compounds . 72 Table 2: Entropy of Binary Metal Oxide Compounds of Li, Be, Mg, At, Si, K, Ti, and Zr and of Elemental Si and K and Some of Their Compounds . 73 References 74 Chap. B4. THERMOCHEMICAL DATA FOR SOME SIMPLE HYDRIDES AND INORGANIC OXIDIZERS (by Donald D. Wagman) 79 1. Introduction 79 2. Hydrides 80 3 . Heavy Metal Hydrides 82 4 . Inorganic Oxidizing Compounds ..... 82 5 . Bibliography 85 V TABLE OF CONTENTS (continued) Page Table 1: Reference Values of Heats of Formation Used In the Calculations ........ 90 Table 2: Selected Values of Heats of Formation of Some Inorganic Hydrides 91 Table 3’ Heats of Formation of Some Heavy Metal Hydrides ...