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1.
Summary It has been observed that mercury can be quantitatively precipitated by Diallyldithiocarbamidohydrazine (Dalzin) at a pH of 3–3.5. It has been separated from nickel, zinc, lead, copper, cadmium and bismuth. The latter three have been kept in solution with the help of EDTA.Part. II: Dutt, N. K., and K. P. Sen Sarma: Anal. chim. Acta (Amsterdam) 15, 102 (1956); cf. Z. analyt. Chem. 155, 353 (1957). 相似文献
2.
Summary Palladium is quantitatively precipitated at aPH 5.0 to 10.1 by 2-mercapto-benzimidazole and the complex, Pd(C7H5N2S)2, which is found to be diamagnetic, is stable up to a temperature of 447 C. In presence of EDTA and tartrate or citrate and at aPH between 6 and 8, it is separated from alkalis, alkaline earths, Mg, Fe3+, Cr, Th, Zr, Ti, UO2
2+, Be, Ce3+, Ce4+, rare earths, Zn, Mn, Ni, Co, Pb, Bi, As, Sb3+, Sn4+, Tl+, Cu2+, Cd, Ir4+, Rh3+, Ru3+, Os4+, CrO4
2–, MoO4
2–, WO4
2–, VO3
–, PO4
3– and AsO4
3–. Pb, Ag and Hg2+ are kept in solution by potassium iodide while a small amount of Au3+ by thiosulphate. The palladium complex is either weighed after drying at 110 C or dissolved in a cyanide solution and determined volumetrically by back titrating the excess cyanide with a standard silver nitrate solution. 相似文献
3.
Summary The reagent 2-mercapto-benzothiazole quantitatively precipitates palladium at a PH 5.6 to 10.2. The red coloured compound, Pd(C7H4NS2)2, is diamagnetic and is stable up to a temperature of 388 C. Palladium is separated from alkalis, alkaline earths, Mg, Fe3+, Cr, Th, Zr, Ti, UO2
2+, Be, rare earths, Ce3+, Ce4+, Zn, Mn, Co, Ni, Pb, Bi, Sb3+, As3+, Sn4+, Tl+, Cu2+, Cd, Ir4+, Rh3+, Ru3+, Os4+, CrO4
2–, MoO4
2–, WO4
2–, VO3
–, PO4
3– and AsO4
3– at apH 6–8 in presence of EDTA and tartaric or citric acid. Besides Pb, Ag and Hg2+ are kept in solution with potassium iodide and Au in a limited quantity forms a soluble complex with thiosulphate. The palladium complex is either weighed after drying and determined gravimetrically or dissolved in an excess of cyanide and determined volumetrically by back titrating the latter with silver nitrate. 相似文献
4.
J. Xavier 《Fresenius' Journal of Analytical Chemistry》1958,163(3):182-187
Summary 2-Mercaptoquinoline is introduced as a sensitive and selective reagent for copper and palladium. Spot test detections and spectrophotometric determinations of these metals have been carried out. 0.03 g Cu at a limiting concentration of 1 430,000 can be detected by the spot technique on a filter paper, and 0.025 g Cu at a limiting concentration of 1 106 by means of the spot plate method. Palladium was determined by measuring the optical density of the orange-yellow colour at 450 m developed in alcoholic medium at pH 1.4–2.8. The sensitivity is 0.009 g Pd per cm2 (Sandell).The author feels deeply indebted to Professor P. Rây, Director and Professor (Hony) of Inorganic Chemistry, for his helpful suggestions, and to Dr. P. C. Banerjee for his kind interest in the work. 相似文献
5.
Several o-hydroxychalcones were examined to develop specific reagents for the precipitation of beryllium in the presence of elements such as aluminium and iron, which occur in its ores. All these reagents showed specificity only in the presence of EDTA. Among them, the readily obtainable 2'-hydroxychalcone is proposed as a new specific reagent for beryllium. The chalcone complex can be dried to constant weight at 105-110 degrees and the conversion factor is 0.01978. A probable structure for the complex has been suggested. Quantitative separation of beryllium from aluminium and iron carried out by this method gave good results. This method was applied for the gravimetric determination of beryllium in beryl and the results were in good agreement with those obtained by the oxide and pyrophosphate methods. 相似文献
6.
Sérgio L. C. Ferreira A. C. Spinola Costa Henrique A. S. Andrade 《Mikrochimica acta》1993,111(1-3):119-125
The reaction between titanium(IV) and 2-(2-thiazolylazo)-p-cresol-(TAC) in aqueous methanol media at apparent pH 4.0–5.6 results in a intensely coloured complex that is stable for at least 2 h. The combining ratio is 1 1 cation TAC. Beer's law is obeyed up to 5.0 g/ml titanium(IV) at 580 nm. The apparent molar absorptivity at 580 nm is 9.82.103 l.mole–1.cm–1 and the detection limit obtained was 5 ng/ml titanium (IV). A spectrophotometric method for the simultaneous determination of titanium and iron with TAC is proposed. 相似文献
7.
The synthesis, characteristics and analytical properties of salicylaldehyde-1-phthalazinohydrazone are described. Spectral characteristics, pK values, the effect of oxidizing and reducing agents, resistance to hydrolysis, and reactions with common cations are reported. 相似文献
8.
Fe(III) undergoes a reaction with colourless Ru(CN)(4-)(6) to produce an intensely violet-blue complex that absorbs at 550 nm and obeys Beer's law over the iron concentration range 0.04-2 mug/ml in acidic medium. Some common cations and anions are tolerable at low concentrations. The procedure is applicable for determination of total iron in potable water. Destruction of organic matter is required for contaminated surface waters or soil samples. 相似文献
9.
Summary Tropolone forms a water-soluble yellow complex with rhodium-(III), which is extractable into chloroform containing pyridine. Although max of the complex lies at 390 nm, the more suitable wave-length for the determination is 420 nm at which there is practically no absorption by the reagent. The composition of the complex, as determined by Job's and logarithmic methods, comes out to be 1 2. The pH range for maximum colour development is 5.5–6.3. Beer's law is followed up to 9.0 ppm and sensitivity of the colour reaction at 420 nm is 0.009g Rh/cm2. The effect of various foreign ions has been investigated. With simple modifications, the method becomes highly selective.
Zusammenfassung Tropolon (Cykloheptatrienolon) bildet mit Rhodium(III) eine gelbe, wasserlösliche Komplexverbindung, die sich mit pyridinhältigem Chloroform extrahieren läßt. Das Absorptionsmaximum liegt zwar bei 390 nm, aber für die Messung eignet sich die Wellenlänge 420 nm besser, die von dem Reagens selbst praktisch nicht absorbiert wird. Die Zusammensetzung des Komplexes wurde nachJob und nach logarithmischen Methoden bestimmt und entspricht dem Verhältnis 1 2. Maximale Farbintensität wird bei pH 5,5–6,3 erreicht. Das Beer'sche Gesetz ist bis 9,0 ppm gültig, die Empfindlichkeit bei 420 nm entspricht 0,009g Rh/cm2. Der Einfluß verschiedener Fremdionen wurde untersucht. Mit einfachen Vorkehrungen wird die Methode hoch selektiv.相似文献
10.
Summary Cobalt(II) gives a deep blue colour with nicotinamidoxime in alkaline aqueous-ethylalcoholic medium which has been used with advantage for the spectrophotometric determination of this metal. The optimum pH for the development of colour is 9.8–11.3 in aqueous-alcoholic (40% v./v.) medium in presence of a large excess of the reagent, at 15–40°C. The colour intensity is measured at 580 m,. Sensitivity is 0.01 g cobalt per cm2, while visual identification limit is 0.5 g cobalt per ml (12·106). Beer's law is obeyed in the range of 0.2–20 ppm of the metal, with an optimum range of 2–16 ppm. The colour is stable for about half an hour in the pN range of 9.8–11.3 and at least one hour in the range of 10.5 to 11.0. On account of the high pN and alcoholic medium used, most of the cations and anions interfere and, hence, must be removed.Part I: See Z. anal. Chem. 168, 326 (1959). 相似文献
11.
Summary The compound bis-salicylaldehyde-ethylenediamine was prepared by the condensation of salicylaldehyde with ethylenediamine. It was crystalline and quite stable. The solution of the compound in caustic alkali was used for the analytical reactions of various ions. Ions of Cu2+, Ni2+, Bi3+, Zn2+, Hg2+, Sb3+, Sn2+ and Ce4+ formed precipitates, while those of As3+ and Pd2+ gave slight turbidity and Fe2+, Pe3+, Co2+ gave colour reactions. Rest of the ions did not respond towards the reagent. The sensitivity of the reactions for Cu2+, Ni2+, Fe2+, Fe3+, Ce4+, Co2+ and Sb3+ was high and their quantitative determinations are possible.
Zusammenfassung Die Verbindung Bis-salicylaldehyd-äthylendiamin wurde durch Kondensation von Salicylaldehyd mit Äthylendiamin dargestellt. Sie ist kristallin und durchaus stabil. Die ätzalkalische Läsung dieser Verbindung wird zu analytischen Reaktionen mit verschiedenen Ionen benutzt. Die Ionen Cu2+, Ni2+, Bi3+, Zn2+, Hg2+, Sb3+, Sn2+ und Ce4+ ergeben Niederschläge, As3+ und Pd2+ geben eine geringe Trübung und Fe2+, Fe3+ sowie Co2+ liefern Farbreaktionen. Die übrigen Ionen sprechen auf das Reagens nicht an. Die Empfindlichkeit der Reaktionen mit Cu2+, Ni2+, Fe2+, Fe3+, Ce4+, Co2+ und Sb3+ ist groß und eine quantitative Bestimmung dieser Ionen ist möglich.相似文献
12.
Summary Lead can be determined from its Bismuthiol II complex volumetrically by dissolving it in an excess of EDTA at a pH of about 10 and titrating the excess of the EDTA against a magnesium or lead solution. In the same way silver can be determined by dissolving the complex in an excess of cyanide and back titrating the excess against a standard silver nitrate with iodide as the indicator. The results of the former are fairly accurate while those due to latter are highly satisfactory with silver less than 20 mg. With higher amounts of silver, however, the results are within +2%.Part VIII see Z. analyt. Chem. 156, 103 (1957). 相似文献
13.
A.G. Asuero 《Microchemical Journal》1978,23(3):390-399
With the purpose of introducing biacetyl bis(2-pyridyl)hydrazone as an analytical reagent, the pyridylhydrazone literature has been reviewed. BBPH acts as a general chromogenic reagent. The fundamental solution chemistry of the complexes formed by BBPH with the metal ions has been studied. BBPH appears to be a promising reagent for the colorimetric estimation of cobalt and palladium. It may be advantageously compared with benzil bis(2-pyridyl) hydrazone which has the same basic chelate structure. 相似文献
14.
Summary Uranium (VI) has been found to give a yellow colour with nicotinamidoxime in alkaline medium which is highly satisfactory for the spectrophotometric estimation of the metal. The optimumph for development of the colour is 10.9–11.5 in presence of a large excess of the reagent, at 10–40C. The colour intensity is measured at 400 m. Sensitivity is 0.045 g uranium per cm2, with a visual identification limit of 5 g uranium per ml. Beer's law is obeyed in the range of 5–40 ppm of the metal with an optimum range of 8–40 ppm. The colour is stable for at least one hour. All the common anions are without effect, excepting however, phosphate, carbonate, and cyanide which are tolerated only in traces. Use of tartrate or EDTA helps to mask effectively all the interfering cations excepting copper, iron and vanadium. 相似文献
15.
Summary Copper has been determined gravimetrically as its bis-salicylaldehyde-ethylenediamine complex of the composition C16H14O2N2 · Cu, dried at 100–120° C. The complex is completely precipitated in theph range of 10.5–13.5, adjusted with ammonia or caustic alkali. It is stable in presence of excess ammonia, 0.1 N alkali, ammonium salts and complexing agents as tartrate, citrate, sodium-thiosulphate, fluoride, thiourea, triethanolamine and EDTA. In presence of tartrate and ammonia the ions of alkali metals, alkaline earths, Ag+, Tl+, Tl3+, Pb2+, Cd2+, Co2+, Mn2+, Pd2+, Al3+, Cr3+, La3+, Ce3+, Au3+, Pt4+, Ti4+, Zr4+, Th4+, UO2
2+ and anions as VO3
–, MoO4
2–, WO4
2–, CrO4
2–, PO4
3–, AsO4
3– do not interfere. Ni2+ and Hg2+ are masked by tartrate, EDTA and ammonia; As3+, Sb3+ and Sn2+ are separated using fluoride as the complexing agent; at an alkalinity of 0.1 N caustic alkali in presence of tartrate As3+, Sb3+, Sn2+, Bi3+, Zn2+ and Fe3+ are separated. Fe3+ can also be separated using triethanolamine as the masking agent at aph of about 13.0. Copper can be separated from almost all the ions, thus affording a highly selective method for the determination of copper.
Part I: Singh, B. R., and S. Kumar: Z. analyt. Chem. 185, 211 (1962). 相似文献
Zusammenfassung Es wird eine gravimetrische Methode zur Bestimmung von Kupfer beschrieben, die auf der Bildung des Bis-salicylaldehyd-äthylendiaminkomplexes beruht. Dieser hat die Zusammensetzung C16H14O2N2 · Cu. Die Fällung wird imph-Bereich 10,5–13,5 (mit Ammoniak oder Alkalilauge eingestellt) vorgenommen und der Niederschlag bei 100°–120° C getrocknet. Der Komplex ist beständig in Gegenwart von überschüssigem Ammoniak, 0,1 n Alkali, Ammoniumsalzen sowie Tartrat, Citrat, Natriumthiosulfat, Fluorid, Thioharnstoff, Triäthanolamin und ÄDTA. In Gegenwart von Tartrat und Ammoniak stören nicht: Alkalien, Erdalkalien, Ag+, Tl+, Tl3+, Pb2+, Cd2+, Co2+, Mn2+, Pd2+, Al3+, Cr3+, La3+, Ce3+, Au3+, Pt4+, Ti4+, Zr4+, Th4+, UO2 2+ sowie VO3 –, MoO4 2–, WO4 2–, CrO4 2–, PO4 3– und AsO4 3+. Ni2+ und Hg2+ können mit Tartrat, ÄDTA und Ammoniak maskiert werden, As3+, Sb3+ und Sn2+ mit Fluorid. In 0,1 n ätzalkalischer Lösung in Gegenwart von Tartrat können As3+, Sb3+, Sn2+, Bi3+, Zn2+ und Fe3+ abgetrennt werden. Fe3+ kann ebenfalls mit Triäthanolamin beiph 13,0 maskiert werden. Das beschriebene Verfahren erlaubt somit eine Abtrennung des Kupfers von fast allen anderen Ionen.
Part I: Singh, B. R., and S. Kumar: Z. analyt. Chem. 185, 211 (1962). 相似文献
16.
In a continuation of earlier work on the reactivity of various isonitrosoacetarylides, the simplest of the series, isonitrosoacetanilide was examined. In acidic medium, this reagent gives a specific reaction with palladium (dilution limit 1:400,000), and in ammoniacal medium a very sensitive reaction with cobalt (dilution limit 1:1,000,000). The composition of the complexes involved was established as R2Pd and R3Co2. The effect of substitution on the reactivity is discussed. 相似文献
17.
18.
2-(8-Quinolylazo)-7-phenylazochromotropic acid (QAPAC) has been synthesized by coupling diazotized 8-aminoquinoline with 2-phenylazochromotropic acid as well as by coupling diazotized aniline with 2-(8-quinolylazo)chromotropic acid. The properties of QAPAC and the spectrophotometric characteristics of some metal-QAPAC complexes are reported. 相似文献
19.
Summary Alkaline solutions of nicotinamidoxime containing traces of nickel(II) give a deep blue color on treatment with iodine. At a pH of 10.5–11.5 in presence of an excess of the amidoxime the color develops almost instantaneously and is stable for at least 24 hrs. The system adheres to Beer's law in the range of 0.3–10 ppm of nickel, and the optimum range for measurement (1 cm cell) is 3–10 ppm of the metal. The color reaction is highly sensitive (spectrophotometric: 0.014 g Ni cm–2 at 575 nm identification limit: 0.5 g Ni ml–1; 12 · 106).All the common anions are without any effect excepting CN– and EDTA which interfere seriously. Interference of Pb2+, Bi3+, Al3+, Ti4+, Zr4+ and Th4+ can be masked by excess tartrate; while in the presence of Cu2+, Co2+, Zn2+, Mn2+ and Fe3+, the Ni2+ is first separated by the anion exchange method of Kraus and Moore
3 and then determined as usual.From the results of polarographic investigations it has been concluded that in alkaline medium nicotinamidoxime is first oxidized possibly to an azo type of compound which interacts with nickel(II) forming the deep blue color.Part II: K. K. Tripathi and D. Banarjea: Z. analyt. Chem. 168, 407 (1959). 相似文献
20.
The synthesis, characteristics and analytical reactions of di-2-pyridyl ketone thiosemicarbazone are described. This compound reacts with iron(II) (λmax=410mm, ε = 9.3 · 103 1 mol?1 cm?1), nickel(II) (λmax =395 mm ε =19.6·103 10 mol ?1 cm -1), cobalt(II) (λmax = 415 nm. ε = 1.0 · 104 mol?1 cm?1 ) and copper(I) (λmax =395mm ε = 11.3 · 103 mol?1 cm?1) A critical comparison of di-2-pyridyl ketone, picolinaldehyde and bipyridylglyoxal thiosemicarbazones as analytical reagents is given. 相似文献