ANALYTICAL C H E M I S T R Y
NEW
Experiments for Instrumental Meth o d s . Charles N. Reilley and Donald T. Sawyer. χ + 412 pages. Mc Graw-Hill Book Co.. 330 West 42nd St.. New York 36, Ν. Υ. 1961. So.On. Reviewed by H. V. Malmstadt, versity of Illinois, Urbana, Ill.
Uni
Although there have been several good " I n s t r u m e n t a l Analysis" textbooks published during t h e past ten years, there have been relatively few carefully planned and tested laboratory experi ments included in them. Therefore, at m a n y schools where courses in instru mental methods are taught, it has been necessary to rely heavily on one's own experiments. I t was the recognition of the lack of sufficient, challenging, re liable, and instructive experiments in a published form t h a t p r o m p t e d the a u t h o r s to write this laboratory m a n ual. Experiments were collected from various schools in addition to those de veloped in the a u t h o r s ' laboratories. In general, the experiments demon strate the basic principles of specific in s t r u m e n t s and their application to chemical problems. I t is necessary, however, for t h e student to evaluate methods on the basis of rather isolated procedures. A few experiments de signed to draw out a critical evaluation and comparison of methods b y t h e stu dent would have been desirable. Ex periments are not included for instru mental methods which require very ex pensive equipment. Therefore, several important areas are not covered such as x-rays, N M R , mass spectrometry, and electrophoresis. E a c h chapter covers a specific in strumental area t h a t is introduced by a brief s u m m a r y of the fundamentals related to the experiments. These sum maries are useful as a quick review of what to look for in the experiments. Elcctrometric, optical, separation, and radiochemical methods are covered in P a r t s I to IV and instrumentation is covered in P a r t V. This final instru mentation section of the book covers t h e properties of electronic components and some elementary considerations of electronic circuits. There is no doubt t h a t after learning the principles and applications of instrumental methods, it is i m p o r t a n t to learn how the circuits in the instruments function and how to keep t h e m working. I n s u m m a r y , this laboratory manual is a useful supplement to a regular text for basic courses in instrumental m e t h
ods. I t includes a large n u m b e r of ex periments t h a t should prove reliable and interesting. An Introduction t o t h e Analysis of Spin-Spin Splitting in High-Resolu tion Nuclear Magnetic Resonance Spectra. John D. Roberts, vii + 116 pages. W. A. Benjamin. Inc.. 2465 Broadway, New York 25, Ν. Υ. 1961. $4.95. Reviewed by P. L. Corio, Mobil Oil Co., Inc., Paulsboro,
Socony N. J.
This monograph gives an elementary t r e a t m e n t of t h e q u a n t u m mechanics of spin coupled nuclei and applies the theory to the calculation of resonance frequencies and signal intensities of some simple spin systems. T h e expo sition is quite brief, consisting of 101 pages of text divided into 4 chapters of approximately equal length. The brevity of the text reflects the limited aims of the author which a r e : " . . . to present a simplified theory of spin-spin splitting for nuclei of spin 1/2 in the hope of providing (1) an introduction to more definitive t r e a t m e n t s and (2) a sound theoretical basis for use of more descriptive approaches." T h e r e is certainly a need for such a text and although the book is princi pally designed for use b y an organic chemist, it can be profitably studied by anyone approaching this subject for the first time. T h e question of need is b u t one aspect of the measure of an introductory text; equally important are the development of ideas and their communication. I t is clear t h a t the a u t h o r has given careful consideration to these problems and their t r e a t m e n t is generally quite good. His success in this connection is largely the result of a shrewd assess ment of those elements of a chemist's background which are relevant t o t h e subject and developed the theory ac cordingly. Although it is not explicitly stated, it is patently a p p a r e n t t h a t this assumed background consists of a fa miliarity with Coulson's Valence. T h e first chapter develops some in t r o d u c t o r y material along with some elementary definitions and conventions. I t is interesting to note t h a t the author, a chemist, takes t h e steady magnetic field in the negative z-direction. On the other hand, physicists prefer to take this field in the direction of the posi tive z-axis. I t t h u s appears t h a t nei ther group is willing lo admit t h a t in
BOOKS an actual experiment the field direction is neither u p nor down b u t sideways ! C h a p t e r 2 begins with qualitative descriptions of the two-spin system for large and vanishingly small chemical shift. This is followed by some formal developments in the theory which are illustrated by calculations of the spec t r a for the AX, A 2 , and AB type spin systems. T h e theoretical develop ments clearly b e t r a y the influence of Coulson's book. For example, the sec ular equation is derived by a varia tional technique while matrix elements and scalar products are defined b y in tegrations over continuous variables rather t h a n t h e conventional summa tions over discrete spin states. T h e use of continuous variables for the de scription of spin states would ordi narily indicate only a preference of one representation over another. In the present case the choice is dictated by pedagogical considerations and a p pears to be the better one. C h a p t e r 3 is concerned with threespin systems; specifically their first order spectra and the A B 2 and A B X systems. C h a p t e r 4 is devoted en tirely to the A 2 X 2 system. T h e text is well illustrated with line drawings, energy level diagrams, and experimental spectra. T h e latter are especially clear since the trace appears in white on a medium gray background with frequencies and line separations in black. M a n y problems are included which expand upon and illustrate the theory and provide practice in its a p plication to the analysis of actual spec tra. T h e only answers given are those supplied gratis in connection with proofs. I n view of the assumed inex perience of prospective readers, it would have been advisable to provide solutions to representative problems. T h e text appears to have been well screened and this reader discovered only one innocuous misprint (p. 61). T h e r e are a few instances, however, in which the formal work could be more precise. On page 31, the interpretation of φ as an angle of rotation about the spin axis would probably cause most physicists to dispair. This classical interpretation, despite its a p p a r e n t in tuitive appeal, is not a valid one since the intrinsic spin vanishes in the classi cal limit: h —> Ο. On the same page, the definition of orthogonality is not at all clear. In lieu of a purely mathe matical definition, an intuitive descrip tion in terms of perpendicularity or, more appropriately perhaps, in t e r m s VOL. 34, NO. 1, JANUARY 1962
·
57 A
NEW BOOKS
TLC
(Thin Layer Chromatography) *
The latest laboratory re
s e a r c h tool (by C a m a g ) for the separation a n d purification of lipids, alkaloids, steroids, etc.
Offers: rapid separation (often less than an
hour), w i d e choice of d e v e l o p i n g reagents, small sample require ments, s h a r p separations. Mechanically—complete control of layer thickness.
Descriptive literature a n d bibliography available from
misco
*Ref Analytical Chemistry, 3 3 , 1138 (August 1961).
MICROCHEMICAL SPECIALTIES CO. 1 8 2 5 EASTSHORE H I G H W A Y
BERKELEY 10, CALIFORNIA
Circle No. 181 on Readers' Service Card
"Ready-to-buy" scientists reach for Analytical Chem istry's A N N U A L REVIEWS & BUYERS' GUIDE through out the year. It uses over 7,000 entries to list more than 600 suppliers within 500 different product head ings.
OUT S O O N ! THE 1 9 6 2 ONE-STOP SOURCE FOR RESEARCH PRODUCTS 58 A
·
ANALYTICAL CHEMISTRY
Now the 1962 edition is in preparation. Published in mid-April, it will go to scientists in 98.2% of all process industry research labs and to the more than 4,250 purchasing agents who place the orders for research products. ANALYTICAL 4 3 0 Park Avenue
CHEMISTRY New York 22
of "non-overlapping" spin functions would be preferable. In connection with the integrations on page 33 it should have been noted that d φ is an abbreviation for άφ1άφΐ . . . . and that the integrations are over all άφν Finally, the variation method, as ordi narily used, gives only approximate re sults. Consequently, it should have been emphasized that in the present instance the method gives the energies and spin functions exactly. The reason for this is that one is not attempting to approximate an oo -dimensional vec tor by a finite expansion; instead one deals from the outset with a finite di mensional space and the form of the correct spin functions is known in ad vance. On the whole, the text is quite good and will undoubtedly be favorably re ceived by many chemists. While it is impossible to predict what a given chemist can learn from this book, it is certainly true that the author's pri mary concern has been the education of his readers and not the impression of colleagues. Treatise on Analytical Chemistry. Part II. Analytical Chemistry of the Elements, Volume 5. xxi + Jfi9 pages. Edited by I. M. Kolthoff and P. J. Elving, with the assistance of Ε. Β. Sandell. Interscience Publish ers, Inc., 250 Fifth Avenue, New York, New York. $16.50 ($13.75 on subscription). Reviewed by Donald T. Sawyer, Department of Chemistry, University of California, Riverside, California. This is the third volume to appear of Part II, Analytical Chemistry of the Elements, of the treatise by Professors Kolthoff and Elving. Earlier reviews of volumes from both Part I and Part II have discussed the scope and philos ophy of the entire treatise. The editors state that "Part II of the Treatise critically reviews the analytical chem istry, inorganic and organic, of all the elements." The present review is concerned with Volume 5 of Part II. The volume con tains five chapters by seven different authors: Titanium (Edward R. Scheffer) ; Zirconium and Hafnium (Richard B. Hahn) ; Thorium (F. S. Grimaldi) ; Nitrogen (A. J. Clear and Milton Roth) ; and Phosphorous (William Rieman III and John Beukenkamp). The high standards set by previous volumes are more than maintained by the present volume. In fact, the de tail and care in reviewing the analytical chemistry of the specific elements ap-
NEW BOOKS pears to bo b e t t e r t h a n in the other two volumes which h a v e been published of l'art I I . Airain the a u t h o r s are highly qualified with specific and extensive ex perience in the analytical chemistry of the element discussed. T h e r e has been a serious need for an u p d a t e d review of the analytical methods available for separating a n d determining the ele ments. T h e present volume satisfies that need and discusses i n s t r u m e n t a l as well as classical methods, and pre sents an objective evaluation of the relative merits of the available proce dures. T h e c h a p t e r s on thorium, nitrogen, and phosphorus are particularly exteiiMve and detailed. B o t h the t h o r i u m c h a p t e r a n d the zirconium-hafnium c h a p t e r discuss and give procedures l'or analyzing the common impurities in the specific elements. T h i s is an added feature which is not found in all of the other c h a p t e r s of Tart I I . In general, this kind of information should prove useful 10 those analytical chemists con cerned with the production and p u r i t y of an element, as well as its compounds and alloys. In s u m m a r y , this volume (and vol umes 1 and 3) will prove invaluable to analytical chemists. T h e extensive bibliographies and the detailed labora tory procedures alone make it an almost essential addition to the analytical chemist's reference library. Again, as with previous volumes, the index for volume 5 is very brief and quite in complete.
Principles a n d Applications of Paper Electrophoresis. Ch. Wundcrly. .tii 4- '.'•'>•> paries. Elsevier Μοιιο(jrajihs. Elseeier Publishing Co., Arris ten hi in, liKil. Sô. 00. Revieived by Paul L. Kirk, University of California, Berkeley, Calif. T h e rapid development of p a p e r electrophorosi.- and its assumption of roles in many phases of routine analysis and in research make the publication of this small volume timely. Its a u t h o r has contributed so extensively to t h e general and specific developments in paper electrophoresis t h a t his evaluation of theory and technique m u s t be considered most a u t h o r i t a t i v e . He has prepared an extended review of the subject, rather than a text. I t should be useful both to the beginner who w ishes to become familiar with the general subject and to the research worker who needs to broaden his a p p r o a c h to analytical problems. It will not be so useful to the routine l a b o r a t o r y as some other publications have been.
T h e book contains five chapters, ranging greatly 7 in length from three pages for C h a p t e r 1 to 95 pages for C h a p t e r δ, this c h a p t e r constituting somewhat more than one half of the text. M o s t extraordinary is the very voluminous collection of 1721 refer ences, still only a portion of t h e flood of papers t h a t have a p p e a r e d on this subject. Some d o u b t m a y be raised regarding t h e cogency of some of the references, which a p p e a r to be of sec o n d a r y significance. Omission of some articles considered to be of value is also noted, n e v e r t h e l e s s , the a u t h o r has performed a major task if he has only scanned rapidly all of the papers he lists. As with most publications in t h e field of electrophoresis, the greater p a r t of the book is devoted to consideration of physiological materials in various liquids of biological origin. Necessar ily, the greatest emphasis is on h u m a n serum proteins. T h e i r variations with race, age, and in disease, and the con ditions u n d e r which they are best sepa rated, stained, and evaluated are dis cussed extensively. Special attention is given to the serious difficulties of ac curate q u a n t i t a t i v e evaluation. All of the other h u m a n body fluids a n d tissue proteins receive attention. A con densed b u t very inclusive review is also included for animal proteins of t h e lower forms, including fish, reptiles, and insects. T h e r e are short discussions of vitamins, mcdicinals, and inorganic m a terials, as t h e y have been studied bymeans of p a p e r electrophoresis. By presenting limited b u t useful theoretical considerations of migration in solid carrier medium, the a u t h o r em phasizes indirectly the fact that theoryis scant in this field as compared with empirical information. Essentially it consists of rational explanations for ex perimental observations, supplemented by consideration of the characteristics of electrophoresis on solid s u p p o r t s as it differs from free b o u n d a r y electro phoresis, for which there is more ade quate theory-. T h e most serious limitation of this volume is its complete preoccupation with p a p e r electrophoresis at a time when other s u p p o r t media are assuming an augmented role. T h e r e is b a r e men tion of starch, agar, polyamide or other gel media, glass paper, and cellulose acetate. T h e justification given is t h a t about 9 0 % of t h e use of electrophoresis employs paper s u p p o r t . Considering t h a t m u c h of this is routine clinical use, and the fact t h a t even in the clini cal laboratory other media are receiv ing increased a t t e n t i o n , this omission appears unfortunate. Certainly, the Circle No. 188 on Readers' Service C a r d —
! Ψ
il ι !
;
111
"Hit ι
Iι ίΐ
1 Am in 11 iili ÏU
'I l!
iflljl' I llh
UNIVERSITIES
The study of NMR as a part of basic chemistry curricula has become more practical, as well as more necessary, with the introduction of the new Varian A-60 Spectrometer. Since the A-60 is simple to operate and provides highly reproducible spectra, all graduate and many undergraduate chemistry students now have an opportunity to become familiar with the analytical capabilities of NMR. But even more important, the chemistry student of today should be prepared to work with NMR after he leaves the university because the A-60 has made NMR analysis routine for process monitoring and quality control—as well as in basic research and analytical laboratories. For complete data on the new A-60 write the INSTRUMENT DIVISION. V A R I A N
associates
611 HANSEN WAY · PALO ALTO, CALIFORNIA
NEW BOOKS
limitations of paper as a support me dium are causing a rapid shift to more satisfactory materials which will set the direction of most of the new devel opment in the electrophoretic field for the foreseeable future. Comprehensive Analytical Chemis try. Volume IB-Classical Analysis.
Edited by C. L. Wilson and D. W. Wilson, xxii + 878 pages. D. Van Nostrand Co., Inc.. 120 Alexander St., Princeton, N. J. 1960. $30.
Reviewed by V. W. Meloche, De partment of Chemistry, The Univer sity of Wisconsin, Madison, Wis. Analytical chemists as well as those who must use analytical methods are placed in an enviable position when they have one source in the literature where they can find the basic informa tion related to the important areas of analytical chemistry. Individual chem ists will vary in their appraisal of the two books published in the proposed
KEWAUNEE SAVES50%of
Kewaunee Auxiliary-Air Type Airflow Fume Hoods operate on a ratio of 5 0 % room air and 50%
auxiliary air. When operating at the minimum face velocity of 50 FPM, these hoods exhaust only 25CFM of air per square foot of sash opening from the laboratory, with the other 25CFM of air per square foot of sash opening obtained from an auxiliary air source. An additional advantage only available with Kewaunee Auxiliary-Air Type Airflow Fume Hoods is that all air (both room and auxiliary) enters through the hood face and is virtually 100% effective in sweeping fumes back to the baffle exhaust openings. Write for complete information on these Air-flow Fume Hoods today !
KEWAUNEE
General Sales Office 3 0 3 0 W . F r o n t St. Statesvllle, N. c .
ADRIAN, KEWAUNEE
MANUFACTURING
TECHNICAL
STATESVILLE,
Circle No. 105 on Readers' Service Card
60 A
.
ANALYTICAL CHEMISTRY
COMPANY
MICHIGAN
N. C.
F U R N I T U R E CO.
series of five volumes. The authors de serve more than mild praise in under taking this formidable job, as well as in the degree of success they have achieved in the preparation of the books already published. Of the five volumes proposed, Volume I deals with Classical Analysis; Volume II, Electri cal Methods and Physical Separation Methods; Volume III, Optical Meth ods; Volume IV, Industrial and Other Specialist Applications ; and Volume V, Miscellaneous Methods and General Index. Volume I is divided in three parts; I A Analytical Processes, Gas Analysis, Inorganic and Organic Quali tative Analysis, and Inorganic Gravi metric Analysis; Volume I B Theory and Principles, Titrimetric Analysis, Apparatus, and Organic Analysis. Each section is supplemented with se lected references from the literature. In Volume I B the authors have pro vided an extensive section on Theory and Principles together with Tables of Physical Constants (185 pages). Chap ters VII and VIII give the reader gen eral principles for the important areas of analysis, selected procedures, limit ing factors and interferences, and se lected references. The authors do not presume that a given procedure can be •applied directly to a given problem. It is recognized that each problem will have its peculiar conditions to which the procedure must be adapted. The discriminating analyst will find that the authors have provided information which will make the choice of the pro cedure less arduous and the solution of his problem more certain. Not all chemists will agree as to the manner in which information is pre sented. In general, the information presented in Chapters VII and VIII leaves little to be desired. However, one may take exception to omissions and commissions, particularly in the section on Theory and Principles. The author takes the view that Normality as an indication of concentration is either out-of-date or of little importance. It seems anomalous that other authors in the same book use Normality. The au thor does not make a strong case for molarity alone (p. 12) particularly since Ε is used to designate the number of equivalents and a few pages later Ε is used in acid-base equilibrium as an error factor (maximum permissible error in one case and permissible error in another). M is defined as moles per liter, yet when the molecular weight of dichromate is used, it must be MW in grams per liter but is not so designated. Most analytical chemists use M, N, or titer to designate concentration and use the one best suited to the problem. Further, in calculations involving com-
peting equilibria, the author evolves a calculation of maximum permissible error but as far as can be determined does not consider calculations based on the method of principle equilibrium. In Chapters VII and VIII little men tion is made of conventional calcula tions and yet this would seem to be an important part of all areas of analysis. Calculations relating to equilibria are only a part of the mathematics of analytical chemistry. This reviewer is not unaware of the difficulties associated with the prepara tion of this book. He is appreciative of the work accomplished but nonethe less has mixed feelings concerning the degree of success the authors achieved.
GET FISHER REAGENTS IN HANDY STORE-POUR POLYP ACS
Characterisation of Organic Com pounds. 2nd Edition. F. Wild, vi + 306 pages. Cambridge University 1'ress. 32 East 57th Street, New York 22. Λ*. 1". 1961. $2.95. Reviewed by R. N. Boyd, Depart ment of Chemistry, Washington Square College, New York University, New York, Ν. Υ. The second edition (1958) of Wild's book, "Characterisation of Organic Compounds/' has now appeared (1961) in a paperback edition at the delight fully low price of $2.95. Whether the binding will hold up under hard usage in the laboratory remains to be seen. At any rate, it should last through a course in qualitative organic analysis, or through several years of research (at which time it could be replaced most inexpensively). The best feature of the book is that it is admittedly restricted to the prepa ration of derivatives, and thus all its 300 some pages can be devoted to this aspect of organic analysis. The result is that discussions of techniques; of difficulties to be expected and how to overcome them; and of how one goes about deciding which derivative to use are much more extensive, enlightening, and useful than in the usual run of analytical texts, whose pages are taken up by classification tests and other pre liminaries. For example, Wild gives detailed information—and advice—on hydrolysis of amides, often a stumbling block to inexperienced analytical stu dents. References to the original literature (one going back to A. W. Hofmann in 1850) are given in the body of the text ; moreover an Author Index is included, in itself a novelty. However, there is no reference later than 1945. If one cannot look to this manual
It's easier, safer to buy reagents in Fisher PolyPacs. You just store a PolyPac until needed, then quickly convert it into a sealed, onthe-shelf dispenser using special pour-spout cap. No need to transfer reagents; no chance for contamination; no deposits, no returns. Fisher's PolyPac is a five-gallon
polyethylene bottle in
sturdy, ICC-approved cardboard carton—pounds lighterthan bulky, expensive carboy it replaces. Among the many liquid reagents available in PolyPacs are formaldehydes, hydrochloric acids, sul furic acids, buffer solutions. Obtain all the facts from your Fisher branch, and ask about getting other reagents in PolyPacs. j .
1 8 9
FISHER SCIENTIFIC World's Largest Manufacturer-Distributor of Laboratory Appliances & Reagent Chemicals Boston . Chicago · Fort Worth . Houston · New York · Odessa, Texas Philadelphia · Pittsburgh · St. Louis · Washington · Montreal . Toronto Circle No. 180 on Readers' Service Card
NEW BOOKS for the latest procedures, then one should expect to find support for the claim in the Preface that many previ ously recorded melting points have been revised, and that "a very large number of new derivatives also have been pre pared and their physical constants listed." However, this reviewer found an unexpectedly large number of gaps in Wild's tables that could be filled in with data already available in other textbooks; whereas Wild's tables were of remarkably little help in filling gaps
*ow
TWO M O D E L S · · ·
in the older books. (The ratio was about 4:1.) It is true, though, that here and there a Table (of compounds and derivatives), for instance, the one for esters, is more extensive than usual. On the other hand, the Tables for amines and for substituted amides, for example, are distressingly short for a book devoted to derivatives alone. One surprising omission is that of a list of alkenes. It is true, too, that some of the types
TWO CAPACITIES . . . m
s
EVERY
N £ f | ) /
THE POPULAR
CENTO-GRAM Unbeatable for general labora tory weighings, specific gravity work, and pre weighing. Portable . . . Adoptable for use in many fields. 311 gram capacity Is higher than any balance of its type through use of two 100 gran» self stored attachment weights. Equipped with stainless steel bows, pan ( 3 % " dia. χ % " aeep) and specific gravity plot» form.
OHAUS THE ALL NEW
This latest OHAUS overhead triple beam balance features 2610 gram capacity, sturdy box end beam, sliding type poise with center indicating panel, self aligning bearings, self storing attachment weights, and specific gravity platform. Available i n ; Model 3600 iMetric) Model 3601 (Avoir,) 65
write for complete
information
OHAUS SCALE CORPORATION COMMERCE
AVENUE
UNION
DEPT. A C Circle No. 51 on Readers' Service Card
62 A
·
ANALYTICAL CHEMISTRY
Quantitative Organic
Microanalysis.
2nd Edition. Al Steyerrnark. 665 -pages. Academic Press, 111 Fifth Ave., New York 3, Ν. Y. 1961. $16.60. Reviewed by Howard J. Francis, Jr., Pennsalt Chemicals Corporation, Philadelphia 18, Pa.
DEC-O-GRAM
1050
of derivatives listed by Wild are not found in the other texts generally avail able. But by and large the number of compounds characterized by any one of them is small. In view of this, and of the numerous gaps mentioned earlier, the claim in the Preface that in this book one can find that "for many of the more important groupings at least one of the series of derivatives is almost complete" is a claim made with equal validity for other books published earlier. The preparations of a number of re agents are given in detail, but in most cases (if not all) these compounds can be readily obtained from commercial sources in the United States. In summary, the discussions about how to choose and prepare derivatives are worth the price of the book. The Tables may, in places, be more accu rate than those found elsewhere, but they are less complete when it comes to the standard derivatives. Numerous types of derivatives are listed here that are not conveniently found elsewhere. Nothing is written about spectroscopic or other instrumental procedures; or about procedures involving titration of derivatives. The references are not up to date. The paper binding may not hold up, but the price is wonderfully low for all the information and help contained therein.
NEW
JERSEY
This is a revised and enlarged edi tion of the author's first book which, since issued, has become not only a standard reference book for the ad vanced worker, but also a textbook used in many colleges and universities engaged in the teaching of microanaly sis. Divided into twenty-three chapters, the contents are arranged in the order of their most frequent use in the microanalytical laboratory. The determina tion of the elements: nitrogen, carbon and hydrogen, sulfur, oxygen, the halo gens, phosphorus, and arsenic, as well as the determination of functional groups and physical properties, is treated with meticulous detail. Much new material has been added in this second edition: a discussion of the value and results of cooperative testing programs, new equipment,
'Om
CURTIN...
MECHROLAB 301 OSMOMETER
•TJJR^NM
di~\
olecular Weight Determination to 20,000 ie M e c h r o l a b 301 O s m o m e t e r fers t h e research and industrial >oratory a fast, accurate and connient i n s t r u m e n t for t h e measure;nt of osmotic concentrations. I t erates by measuring· t e m p e r a t u r e Terences, caused by differential iss transfer, between a sample op of test solution and a reference ap of pure solvent. ^ST—CONVENIENT. A unique îthod of applying t h e sample to e t h e r m i s t o r bead permits measements on a new sample about ery two minutes. X U R A T E . Matched thermistors, simple d-c bridge circuit and a null iicator permit measurement of •nperature differences of t h e order 0.01- C with an accuracy of 1 % . ith organic solutes in benzene, )lccular weights up to 5000 can be jasured with 1% accuracy. Temperature of t h e t h e r m i s t o r vironment is controlled to b e t t e r an ± 0 . 0 0 1 r i C. The Model 301 •mometer is designed for connient bench top use. talog No. 16830
Each 1850.00
For complete information write . H. Curtin and Company, P . O. >x 118, Houston 1, Texas.
W.H.CURTIN & CO. ·. LABORATORY APPARATUS, FURNITURE & CHEMICALS
Circle No. 24 on Readers' Service Card
NEW BOOKS changes and revisions of older procedures, a n d several completely new sections such as t h e determination of fluorine, t h e oxygen flask combustion procedure, the thermistor-isothermal distillation m e t h o d of molecular weight determination, and a greatly enlarged section on t h e use of microhydrogenation as a functional determination. B y carefully carrying out t h e instructions of t h e a u t h o r , any person of normal skill and dexterity should be able to carry out the common operations of t h e microanalysis. M e t h o d s and equipment have been described in detail. I n those cases where t h e geometry of the equipment is a critical factor detailed drawings and specifications needed for its duplication are included as well as suggestions on commercial sources of supply. E a c h c h a p t e r is concluded with a discussion of references pertinent to t h e particular determination. The m a n n e r of citation of this additional material has been changed from t h e reiterative prose style to a t a b u l a r form. References have been included u p to 1960, and t h e a u t h o r has been signally honest in giving credit to word-ofm o u t h information which is so common among microanalysis. This book is clearly and a u t h o r i t a tively written. T h e s t u d e n t of microchemistry, as well as t h e practicing analvst will find this book invaluable.
I I
ι
ιI
,
liiiiililiii .,§
; |,l ||l' "H'V
I
Government Publications Nuclear Science Series The following are additions to previonshj published, lists in ANALYTICAL C H E M I S T R Y (latest one December l!)isi, page 7S A). These are available from, the Office of Technical Services. Washington 25, D. C. The Radiochemistry of Tellurium. G. W. Leddicotte, Oak Ridge National Laboratori/, NAS-NS 303S. Jt2 pages. July 1961. 50 cents. The Radiochemistry of Niobium and Tantalum. E. P. Steinberg, Argonve National Laboratory. NAS-NS 303,9. 57 pages. August 10(i1. 75 cents. The Radiochemistry of Lead. ΙΓ. Μ. Gibson. Bell Telephone Laboratories. NAS-NS 3040. 15S pages. August 1061. S 1.75. The Radiochemistry of Cobalt. L. C. Bate and G. W. Leddicotte. Ο ah Ridge National Laboratori/. NASNS 3041. 90 pages. September 1961. $1.00. Circle No. 187 on Readers' Service Card —
Although both NMR and infrared are valuable for determining the nature and structure of organic compounds, each measures totally different prop erties of molecules. Because of this difference in approach, a •chemical environment that causes a serious interference and ambiguity in infra red may create no difficulties at all for NMR, The new easy to use Varian A-60 has now made routine NMR analysis fea sible by providing highly reproducible spectra on pre-calibrated charts. NMR spectra can be collected, cata loged and used much the same way as infrared. With both spectroscopic techniques available in your laboratory, you can solve a much greater range of prob lems, more conveniently and with greater certainty. V A R I A N
associates
611 HANSEN WAY · PALO ALTO, CALIFORNIA
NEW BOOKS
Calibrated Current Source for testing ELECTROMETERS!
The Radiochemistry of Tungsten. IT. T. Mullins and G. W. Leddicotte, Oak Ridge National Laboratory NAS-NS '3043. 40 pages. Septem ber 1961. 50 cents. The Radiochemistry of Germanium, J. A. Marinsky. University of Buffalo. NAS-NS 3043. 4S pages. July 1961. 50 cents.
Gyra CS-51 Current Source . . offers a convenient method of verifying ELECTROMETER calibration . . . essential for accurate Gas Chromatog raphy and other applications of ELECTROMETERS! Pro vides 70 accurately calibrated increments of current between 1 μμα and 10,ua for checking the electrometer input tube sensitivity, (which may have been overload ed with resultant loss of emission on a preceding ap plication) thermal drift and other causes of calibration deviations. Current is derived from self-contained mercury cells. Write for Gyra CS-51 Bulletin No. 700. Other products of Gyra Electronics Corporation are Electrometers, and stabilized power supplies for laboratory research.
Gyra
C
ELECTRONICS CORPORATION
Phone: FLeetwood 4-4644 P.O. Box 184 A2 LaGrange, Illinois Circle No. 29 an Readers' Service Card
AND
The Radiochemistry of Platinum. G. W. Leddicotte, Oak Ridge Na tional, Laboratory. NAS-NS 304430 pages. October 1961. 50 cents.
Correction Standards for Indicating and Re cording Instruments and Auto matic Controls for Industry. Re corder-Controller Section. Scientific Apparatus Makers Association. 370 Lexington Ave., New York 17. Ν. Υ. 25 cents each. Between the period 1054 to 1001 the Recorder-Controller Section of the Scientific A p p a r a t u s M a k e r s Associa tion has issued a total of 14 s t a n d a r d s . Six of these are SAM A S t a n d a r d s : eight others are listed as SAMA T e n t a t i v e S t a n d a r d s . T h e l a t t e r group remains as such for a period of two years from date of adoption, at the end of which time t h e y a r c considered for adoption as SAMA S t a n d a r d s . I n the Decem ber issue (page 74 A) the price cited failed to indicate t h a t the 14 s t a n d a r d s cost 25 cents each. E a c h of the Stand ards listed below, therefore, cost 25 cents. SAMA Industry Standards RC RC
in a HAWS Emergency Drench Shower. Burning, corrosive, caustic c o n t a m i n a t i o n can inflict injuries m o r e d a n g e r o u s than blazing clothing! C o n t a m i n a t i o n by acids, chemicals, volatile fuels. radioactive elements, etc., m u s t be i n s t a n t l y c o u n t e r e d by first did. I m m e d i a t e d r e n c h i n g with clear water is the first precaution against p e r m a n e n t injury. H A W S leads in design and p r o d u c t i o n of Emergency Drench Showers! Ask for our complete catalog.
RC RC RC RC
Model 8590 Multiple nozzle shower drenches victim from all angles.
Since 1909 a product of HAWS DRINKING FAUCET COMPANY 1443 Fourth St., Berkeley 10, Calif. Circle No. 34 on Readers' Service Card ·
ANALYTICAL CHEMISTRY
Mechanical and Electric Chart Drive Speeds of Circular Charts 2. Air Pressures for Pneumatic Controllers and Transmission Systems 5. Resistance Thermometers 9. Tomperature-emf Relation for Iron-Constant an Thermo couples 10. Locks and Keys for Instrument Cases 11. Mechanical Chart Drives
SAMA Tentative Standards
DRENCH SHOWERS
64 A
1.
RC
3.
RC RC RC
4a. 6b. 7a.
RC
8a.
R C 12. RC 17. R C 18.
Accuracy and Sensitivity Ter minology as Applied to In dustrial Instruments Bimetallic Thermometers Filled System Thermometers Liquid-in-Glass Industrial Thermometers Thermocouple Thermometers (Pyrometers) Panel Cut-Out Dimensions Bushings and Wells for Tem perature Sensing Elements Markings for Adjustment Means in Automatic Con trollers
