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1.
N-Benzoylphenylhydroxylamine has been employed in the gravimetric determination of beryllium and in its separation from iron, aluminium and titanium. After suitable adjustment of pH iron, aluminium or titanium is precipitated quantitatively with the reagent; beryllium is subsequently precipitated after raising the pH of the filtrate. The metal may be determined by either igniting the precipitate to beryllium oxide or weighing it as Be(C13H10O2N)2. 相似文献
2.
Summary An organic reagent viz. acetoacetanilide has been found out which precipitates beryllium quantitiatively aboveph 5.5. The complex, Be(C12H10O2N)2, containing 2.49% Be can be weighed directly after drying. Beryllium can be precipitated from solutions containing aluminium and iron by masking these foreign elements with EDTA. A method has also been described for the determination of beryllium content in beryl.
Zusammenfassung Beryllium kann oberhalbph 5,5 mit Acetoacetanilid quantitativ gefällt werden. Der gebildete Komplex, Be(C10H10O2N)2, der 2,49% Be enthält, kann gleich nach dem Trocknen gewogen werden. Die Gegenwart von Aluminium und Eisen stört nicht, wenn äDTA als Maskierungsmittel zugegeben wird. Die Bestimmung von Beryllium in Beryll wird ebenfalls beschrieben.相似文献
3.
Summary Beryllium has been determined with cupferron by precipitating the metal at pH 5.8. The complex can be weighed directly as Be (C6H5O2N2)2 containing 3.18% of the metal after drying at 110°C. The metal has also been separated with cupferron masking iron (III), aluminium, cerium, thorium, copper, nickel, cobalt, zinc and cadmium with EDTA The beryllium content of beryl has been determined in the same way.
Zusammenfassung Zur Bestimmung von Beryllium wird mit Kupferron bei pn 5,8 gefällt und der Komplex Be (C6H5O2N2)2 (mit 3,18% Be) nach Trocknen bei 110°C direkt ausgewogen. Eisen(III), Aluminium, Cer, Thorium, Kupfer, Nickel, Kobalt, Zink und Cadmium können mit ÄDTA maskiert werden. Auf diese Weise wurde auch der Be-Gehalt von Beryll bestimmt.相似文献
4.
Summary The micro determination of P2O5, Al, Fe, Be, and Mg have been investigated to determine their applicability to a system of separation. In the case of magnesium
and beryllium new methods of determination were worked out. A plan of separation of these ions has been suggested. The conclusions
set forth in this paper are based on experimental data secured through numerous determinations. These determinations involved
about one hundred macro and over three hundred micro weighings. The authors are at present continuing the work of carrying
out a complete separation of all ions listed above. 相似文献
5.
Beryllium oxinate has been proeipitated from homogeneous solutions and the nature of the complex has been studied by thermo gravimetric, infrared and X-ray methods. A structural formula has been proposed on the basis of the results. 相似文献
6.
Caesium can be determined gravimetrically with sodium triphenylcyanoborate (Caesignost) as precipitant. The precipitation was checked by addition of (137)Cs tracer and gamma-spectrometry. The following parameters were studied: temperature, digestion time, influence of potassium on the precipitation of caesium, and separation of caesium from bulk quantities of potassium. 相似文献
7.
Summary The scope of complexone (disodium salt of ethylenediamine tetraacetic acid) as masking agent has been further extended. Uranium is estimated as oxinate in presence of Th, R. E. and Zr. Uranium is also estimated in presence of 100 mg. of Th, and 30 mg. of R. E. respectively in presence of 100 mg. of P2O5. Uranium has been separated from V2O5 by reducing the latter in mild acid solution with complexone itself. 相似文献
8.
A gravimetric determination of tin is proposed with sodium cyclotetramethylenedithiocarbamate as precipitant at pH 5.0–5.5. By optimizing the reaction conditions the theoretical conversion factor 0.1687 can be used for determining ≥5% of Sn. Its standard deviation (n=10) at the level of 20 mg of Sn was found to be 0.08 mg. Effects of diverse cationic species can be eliminated by a clear-cut group precipitation at pH 9 with DDTC in the presence of tartrate and subsequent masking with EDTA. Provision is also made for removal of individual species in occasional cases. Hence, the proposed method is flexible and versatile and was successfully applied to the macro-determination of Sn in diverse alloys. 相似文献
9.
The sodium salt of N-(N-bromo-C-tetradecyl betainyl)-C-tetradecyl betaine is presented as a gravimetrie reagent for the determination of gold. Two complexes have been isolated; one, precipitated from hydrochloric acid solution, containing 22.14% gold; the other, from hydrobromic acid solution, containing 18.01% gold. Both complexes may be dried to constant weight at 85° C, thus giving the advantage of a favorable weight factor. Determinations from hydrobromic acid solutions are more rapid and offer several other advantages. Optimum conditions have been established. The number of interfering ions is small and a method for thie separation of gold from these ions was developed. A procedure for the determination of gold in ore concentrates was applied to several samples with satisfactory results. 相似文献
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Agrawal YK 《Talanta》1973,20(11):1213-1215
A quantitative gravimetric determination of cadmium in presence of Ag(+), Be(2+), Pb(2+), Mn(2+), Ni(2+), Cu(2+), Zn(2+), Hg(2+), Pd(2+), Ga(3+), Al(3+), Bi(3+), Sb(3+), La(3+), Ti(4+), Zr(4+), V(5+), Mo(6+) and U(6+) was made by selective precipitation with N-phenylbenzohydroxamic acid from a solution containing 6-15 mg of cadmium acetate at pH 5.8-6.5. The precipitate was weighed directly after drying at 110-120 degrees . The cadmium complex is curdy white, granular and melts at 225 degrees. The analytical results indicate the complex to be (C(13)H(10)NO(2))(2)Cd. 相似文献
15.
Biguanides are interesting reagents for the determination of palladium owing to their solubility, chemical resistance, and selectivity in moderately acidic solutions. A procedure for the gravimetric determination of palladium(II) in the form of Pd(HL)2SO4, where HL = biguanide, is proposed and the conditions of precipitation, treatment of the precipitate, precision, accuracy, and selectivity of the procedure are discussed. 相似文献
16.
Summary Acetoacetanilide reacts with bromine in presence of acid to form a dibromo derivative. Of the two bromine atoms only one is attached to the benzene nucleus and probably the other is attached to the reactive methylene group, the last replacement being reversible. On addition of excess of bromate-bromide mixture to acidified solution of acetoacetanilide and subsequent titration with sodium thiosulphate it has been found that the addition of bromine is quantitative, and one acetoacetanilide molecule is equivalent to two bromine atoms.This property has been utilised in volumetric determination of beryllium. Beryllium is precipitated with acetoacetanilide and the complex is dissolved in hydrochloric acid. By the measurement of bromine absorbed by the acetoacetanilide thus liberated, the amount of beryllium can be determined.The method is applicable to the determination of beryllium in presence of aluminium and iron provided EDTA is added during precipitation and also to the determination of beryllium content of beryl.
Zusammenfassung Acetoacetanilid reagiert mit Brom in saurem Medium zu einem Dibromderivat. Das eine Br-Atom tritt dabei an den Benzolkern, während das andere wahrscheinlich von der aktiven Methylengruppe (reversibel) gebunden wird.Durch Zugabe von überschüssiger Bromat-Bromidlösung zu einer angesäuerten Lösung von Acetoacetanilid und nachfolgende Titration mit Thiosulfatlösung wurde festgestellt, daß die Bromaddition quantitativ verläuft und ein Molekül Acetoacetanilid zwei Bromatomen äquivalent ist.Diese Reaktion wurde zur volumetrischen Bestimmung des Berylliums benutzt. Hierbei wird das Beryllium mit Acetoanilid gefällt, der Niederschlag in Salzsäure gelöst und der Bromverbrauch des so freigesetzten Acetoacetanilids gemessen. Daraus ergibt sich die Menge an Beryllium.Das Verfahren kann auch zur Berylliumbestimmung in Gegenwart von Aluminium und Eisen verwendet werden, wenn man bei der Fällung ÄDTA zugibt. Die Be-Bestimmung in Beryll wird ebenfalls beschrieben.相似文献
17.
A method is established for the spectrophotometric determination of small amounts of beryllium as a 1:1 complex with Calcichrome in slightly acidic solution. Beer's law is obeyed over the range 0.05-0.6 ppm Be in the final solution and the apparent molar absorptivity is 9.7 x 10(3) l.mole(-1). cm(-1) at 625 nm. Up to about 15 mug of beryllium in the final solution can be sensitively and selectively determined with a relative error of less than 2% in the presence of EDTA as masking agent. 相似文献
18.
A method is described for the precise determination of small amount of aliphatic alcohols in esters. The procedure is based on the formation of a red-coloured complex between the alcohol and a solution of vanadium oxinate in nitrobenzene. Studies have been made on the effect of solvent, reaction time and the stability of the complex on the accuracy of the determination. 相似文献
19.
Di-2-thienylketoxime may be used as a gravimetric reagent to determine gold. The error is of the order of ± 0.3%. There are few interfering ions and simple methods may be used to eliminate these. 相似文献