ANALYTICAL CHEMISTRY
1188 Sensitivity of Color Reaction. Sensitivity measurements were carried out in 50-ml. Nessler tubes, using the same quantity of reagent ~olutiouin the blank. It was found that the smllest amount of vanadium that oould be detected with bensoylphenylhydroxylrtmine was 0.33 mg. in 1liter of solution. CONCLUSIONS
Beneoylphenylhydroxylamin~ provides a simple and sensitive method for the colorimetric determinetion of vanadium. Moreover, this organic reagent can be prepmed easily and preserved indefinitely. Vanadium can be estimated in presence of certain ions, hut iron and aluminum, even in traces, interfere with the procedure. Further work will he required to eliminate the interferences caused by iron and aluminum which are commonly associated with vanadium. ACJCNOWLEDGMMT
The author wishes to express his sincere thanks t o Sir J. C. Gbosh, director, Indian Institute of Science, for the opportunity
to carry out this investigation and to S. C. Bhrtttaeharyya for his suggestions and help. LITERATURE CITED
fli , . Baoh. J. M..and Trelles.R. A.. Bol. obras sanit. nacidn iBuenos ~ i A ) , 5i27 , (1941). ( 2 ) Bamberger,E.,Bel., 52,1116 (1919). (3) Chewakov, N. I., and Ostroumov. E. A,, Zavodskaya Lab., 3, x..m. iim41. ~...~,. (4) Findlay. S. P., and Furman, N. H.,Manhattan District, Document M.S.A.4.-2900 (1945). ( 5 ) Furman, N. H., Meson, W. B., and Pekola,J. S., ANAL.CHEM.. 21,1325(1'340). (6) Gregory, A. W., Chem. Mews. 100. 221 (1009). (7) Meaurio, V. L., Ann. chim. anal., 23,47 (1918). (8) Molland, J., Compt. rend., 210, 144 (1940). (9) Montequi, R.,and Gallego, M.,Andes. SOC. espaii.As. p " h ,32. 134 (1934). (10) Shome, S.C.,Ambsl. 75,27 (1950). (11) Shome, S. C., Current Sci.. 13,257 (1944). (12) Snell, F. D.,and Snell. C. T., "Colorimetric Methods of Andyais,"p. 372, New York, D. Van Nostrand Go., 1936. (13) SuebellBdy,L..and Ajtai, M., Mik~ochemie,26, 87 (1930). (14) Zilberminte,V. A,, and Florenskii, K.P.,Ibid., 18, 154 (1035).
1,s-Dinitronaphthalene I
47.
Contributed by WALTER C. McCRONE, Armour Research Foundation of Illinois Institute of Technology, Chicago 16, 111.
XCELLENT crystals of 1,S-dinitronaphphthalene can be ob-
E tained from alcohol or benzene.
Crystals from benzene lie preferentially on the basal pinacoid. On a micraswpeslide thymol e m he used to give perfectly formed crystals for morphological and optical study (Figure 1).
dome, loll), are also usually present; from benzene the basal pinacoid, (001/, is thedominant form. Axial Ratio. a:b:c = 0.758:1:0.359, 011 A Oil Interfacial Angles (Polar). 110 11 110 = 74'20'; = 39' 26".
data). Formula Weight. 218.16. Density. 1.587 (flotation and pycnometer); 1.591 (calculated from x-ray data). Principal Lines d
7.52
6.27
'
A
5.72 5.34 5.09 4.87 4.63 4.34 4.11 3.92 3.80 3.67 3.47 3.08 3.04 2.97
/ i
A.
0.8
0.8
0.1 0.2 0.2 0.7 very weak 0.2
0.2
0.9 Very weak 0.2
0.1 1.0 Very weak
d 2.85 2.77 2.71 2.67 2.64 2.55 2.48 2.44 2.38 2.33 2.26 2.22 2.19 2.14 1.89 1.87
IfIi 0.6 0.8 Very weak Very weak Very weak Very weak 0 3 0.2 Very weak Very weak 0.5 Very weak Very wesk Very weak 0.05
0.05
B
Figure 1. 1,s-Dinitronaphthalene B.
I .~ f& 0.3
Form I1 growinq fmm melt Form I crystallized from thymol on miomsoope slide
Although l,%dinitronaphthalene has a t least two unstable plymorphic forms, the latter have been obtained only from the melt on a microscope slide. CRYSTAL MORPHOLOGY Crystal System. Orthorhombic. Form and Habit. From alcohol as flat rhombs lying on the macropinamid, {lWI;the prism form, I l l O ) , and the brschy-
OPTICAL PROPERTIES Refractive Indexes (5893 .4.; Z5O C,). a = 1.634 =k 0.002. 8 = 1.763 =t0.005. y = 1.86 (calculsted from a,8,and 2V). Ontic Axial Andes. 15893 9.:25" C.). 2V = 80'. Dkersion. Very stronp, v >'r Optic Axial Plane. 0011 Sign of Double Refraction. Segative. bmbe Bisectrix. a = a. Molecular Refraction ( E ) (5893 8.;25' C,), = 1.750. R(ca1cd.) = 54.1. R(ob3d.j = 56.0.
q a x
V O L U M E 23, NO. 8, A U G U S T 1 9 5 1
111. Form I11 is formed if the preparation is chilled rapidly, although some Form I1 is almost always present. Form I11 forms long broad rods with unique mechanical twin bands forming on cooling (these disappear on heating and reappear on cooling). The interference figure is either an optic normal or an obtuse bisectrix figure. Occasionally a rhomb-shaped crystal appears embedded in these rods. The rhomb shows no inclination to transform or grow and may be another view of Form I11 (if not, it is Form IV). It shows a centered B X , figure, 2E ea. 60°, 2. > r, the optic axial plane bisects the acute profile angle of 55
g-); .
1189
Form I cannot be obtained from the melt. All attempts lead to Form 11, since Form I changes to Form I1 a t the transition temperature of about 110” C. Recrystallization from thymol leads often to a rather startling solid solid transformation, probably of Form I11 to 11. Long rods grow as the melt cools until suddenly each gives a tremendous shiver as it twists and bends during transformation. 1,8-DIIVITRON4PHTHALEYE 11
CRYSTALMORPHOLOGY. Crystal Svstem. Orthorhombic. FoEm and Habit. Crystallizes from thymol on a microsco e slide as rhombs similar in appearance to Form I, except that tge rhomb profile angle is 55’ and that view shows crossed axial plane dispersion. OPTICALPROPERTIES.
C
Dispersion of Optic Axes of 1,8-Dinitronaphthalene I1 FVave Length, A. 6360 6140
5930 5720 5500
a
I
2E 27’ 250 23‘ 200
Wave Length, A. 5370 5290 5070 4860
110
Sign of Double Refraction.
2E
-::1 - 18: - 32
Segative.
1,8-DINITRONAPHTH 4 LER E
A4tleast one additional unstable modification is obtained on crystallization from the melt or from thymol solutions on a microscope slide. Everything known about this very unstable form is included under fusion data for Form I. ACKNOWLEDGMENT
Figure 2. Orthographic Projection of Typical Crystal of 1,8-Dinitronaphthalene As recrystallized from thymol on a microscope slide
The crystals from the melt nearly always show some Form I1 and never show Form I. Form I1 is characterized by large globular areas of uniform polarization color, often a deep blue or purple. The latter corresponds to the centered acute bisectrix view. The figure shows crossed axial plane dispersion with 2E very low, ( - ).
+
Metal Spectroscopy. F . Twyvaan. vii 569 pages. Charles Griffin & Co., Ltd., 42 Drury Lane, London WC2, England, 1951. Jarrell-Ash Co., Boston, Mass. Price, S8.75. Although ostensibly a comprehensive treatise on the spectrochemical analysis of metals, this work is especially interesting and enjoyable as a character sketch of the author and as an outline of his more than fifty years of outstanding contribution to this field. Essentially British, slightly provincial, and markedly Hilgeresque, the book provides an excellent historical background and is replete with lore of spectroscopy of earlier times. The development of the art and science of emission spectroscopy up to about 1945 is covered to an excellent degree of completeness and expertness. The treatment of developments from 1945 up to the date of publication is rather fragmentary, incomplete, and rather uncritical with the exception of the several narrow fields covered by the collaboratory authors. The book can be regarded as representing authoritative British opinion as of 1945 plus a certain amount of selected descriptive material on later developments.
This description is based on preliminary work carried out at Cornell University under contract OEMsr-193 viith the OSRD during 1943-44 under the administ,rative direction of Alfred T. Blomquist. John H. .Indreen and Sien-Moo Tsang were associated m-ith this project and contributed to the above descript ion. COSTRIBUTIOSS of crystallographic d a t a for this section should be sent to F a l t e r C. hIcCrone. supervisor, Analytical Section, h r m o u r Research Foundation of the Illinois Institute of Technology, Chicago, I11
Twyman has made an obvious and generally successful attempt to be fair and objective in his comparative treatment of commercial instruments. His frank and frequent use of the first person singular and the frequency of such phrases as “when I designed the instruments from TThich all modern quartz spectrographs for metallurgical work are derived” are probably more than justified by historical fact. As a loyal member and leader of the old guard, Twyman is still fighting the battle of the prisms versus the gratings and is not yet ready to grant the comniercial supremacy of gratings so evident in the United States. His former opposition to microphotometers as practical analytical devices has almost completely disappeared and there remains in this book only a nostalgic comment on the failure of the logarithm sector to obviate the necessity for such instruments. -4merican readers may be annoyed by the author’s continued adherence to galvanometer deflection ratios in place of the more elegant and precise methods of calibration generally used in the U.S.A. The latter are described in brief, but the author implies that he believes most practical analysts restrict measurements to the “straight-line” portion of the emulsion calibration curve.
