Spectrophotometric determination

PAM,. spectropliotoniciric dctcrniination of vanadium photometric dctenniiiation of niobium in the presence of trietlianolamine spectrophotomelric determination of bismuth in the presence of 1,3-diphenylguanidinc spectrophotometric determination of yttrium in the presence of Ttephiramine formation constants of mmplexes with Hoflll) measured... [Pg.158]

Gives complexes of constrating colors with AI,Zn, Th. Zr, and Ga and is useful in tlie photometric analysis of these elements specific reagent of Pa(H) spectrophotometric determination of Cu(U)... [Pg.161]

This experiment demonstrates the chemical limitations to Beer s law using the NO2-N2O4 equilibrium as an example. Blanco, M. Iturriaga, H. Maspoch, S. et al. A Simple Method for Spectrophotometric Determination of Two-Components with Overlapped Spectra, /. Chem. Educ. 1989, 66, 178-180. [Pg.447]

Mehra, M. C. Rioux, J. An Analytical Chemistry Experiment in Simultaneous Spectrophotometric Determination of Fe(III) and Cu(II) with Hexacyanoruthenate(II) Reagent, /. Chem. Educ. 1982, 59, 688-689. [Pg.447]

In the process of performing a spectrophotometric determination of Ee, an analyst prepares a calibration curve using a single-beam spectrometer, such as a Spec-20. After preparing the calibration curve, the analyst drops the cuvette used for the method blank and the standards. The analyst acquires a new cuvette, measures the absorbance of the sample, and determines the %w/w Ee in the sample. Will the change in cuvette lead to a determinate error in the analysis Explain. [Pg.450]

Quantitative. Classically, silver concentration ia solution has been determined by titration with a standard solution of thiocyanate. Ferric ion is the iadicator. The deep red ferric thiocyanate color appears only when the silver is completely titrated. GravimetricaHy, silver is determined by precipitation with chloride, sulfide, or 1,2,3-benzotriazole. Silver can be precipitated as the metal by electro deposition or chemical reduciag agents. A colored silver diethjldithiocarbamate complex, extractable by organic solvents, is used for the spectrophotometric determination of silver complexes. [Pg.91]

O. Valcl, 1. Nemcova, and V. Suk, Handbook ofTriarjlmethane andHanthene Djes Spectrophotometric Determination of Metals, CRC Press, Inc., Boca Raton, Fla., 1985. [Pg.277]

Bromide ndIodide. The spectrophotometric determination of trace bromide concentration is based on the bromide catalysis of iodine oxidation to iodate by permanganate in acidic solution. Iodide can also be measured spectrophotometricaHy by selective oxidation to iodine by potassium peroxymonosulfate (KHSO ). The iodine reacts with colorless leucocrystal violet to produce the highly colored leucocrystal violet dye. Greater than 200 mg/L of chloride interferes with the color development. Trace concentrations of iodide are determined by its abiUty to cataly2e ceric ion reduction by arsenous acid. The reduction reaction is stopped at a specific time by the addition of ferrous ammonium sulfate. The ferrous ion is oxidi2ed to ferric ion, which then reacts with thiocyanate to produce a deep red complex. [Pg.232]

Choline reineckate is used in the spectrophotometric determination of choline. Ammonium reineckate [13573-16-5] forms a water-insoluble complex with choline. The complex is soluble in acetone and a widely used method for determination of choline is by light absorption of acetone solutions... [Pg.101]

Z. Marczenko, Separation and Spectrophotometric determination of Elements, Fllis Horwood Ltd., West Sussex, UK, 1986. [Pg.382]

Z. Marc2enko, Separation and Spectrophotometric Determination of Elements, Ellis Horwood Ltd., West Sussex, UK, 1986 E. B. SandeU, Colorimetric Determination of Traces of Metals, Interscience Publishers, New York, 1959. [Pg.259]

INDOLIUM AND BENSTHIAZOLIUM AS A NEW HIGHLY SENSITIVE REAGENTS FOR THE SPECTROPHOTOMETRIC DETERMINATION OF NITROPHENOLS... [Pg.53]

SPECTROPHOTOMETRIC DETERMINATION OF PHOSPHATE AND ARSENATE IONS BY MEANS OF IONIC ASSOCIATES OF CYANINE DYES WITH POLYOXOMETALATES... [Pg.87]

A reaction of mixed molybdenum polyoxometalates (POMs) with cyanine dye has been used for highly selective and sensitive spectrophotometric determination of phosphorus(V) and arsenic(V). Color of the solution is considerably changed by reaction of Keggin POMs with styrene cyanine dyes. Derivatives of l,3,3-threemethyl-3//-indol - astrazone violet (AV 3R), astrazone rose, astrazone yellow, astrazone red were investigated. [Pg.87]

SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION OF BROMIDES AND IODIDES IN BROMIDE-PREVALENCE... [Pg.97]

PROPERICIAZINE AS A SELECTIVE AND SENSITIVE REAGENT FOR THE SPECTROPHOTOMETRIC DETERMINATION OF MICROGRAM AMOUNTS OF PLATINUM... [Pg.117]

EXTRACTION-SPECTROPHOTOMETRIC DETERMINATION OF PHOSPHATE AND ARSENATE USING IONIC ASSOCIATES OF POLYOXOMETALATES WITH BASIC DYES... [Pg.125]

Two procedures for the extraction-spectrophotometric determination of P(V) and As(V) have been developed. [Pg.125]

The procedure of simultaneous extracting-spectrophotometric determination of nitrophenols in wastewater is proposed on the example of the analysis of mixtures of mono-, di-, and trinitrophenols. The procedure consists of extraction concentrating in an acid medium, and sequential back-extractions under various pH. Such procedures give possibility for isolation o-, m-, p-nitrophenols, a-, P-, y-dinitrophenols and trinitrophenol in separate groups. Simultaneous determination is carried out by summary light-absorption of nitrophenol-ions. The error of determination concentrations on maximum contaminant level in natural waters doesn t exceed 10%. The peculiarities of application of the sequential extractions under fixed pH were studied on the example of mixture of simplest phenols (phenol, o-, m-, />-cresols). The procedure of their determination is based on the extraction to carbon tetrachloride, subsequent back-extraction and spectrophotometric measurement of interaction products with diazo-p-nitroaniline. [Pg.126]

ELUCIDATION OF THE HETEROPOLYBLUE NATURE AND EXTRACTION-SPECTROPHOTOMETRIC DETERMINATION OF PHOSPHATE USING MIXED HETEROPOLYANIONS... [Pg.156]

Ln(II) in LnFj Ln(II) were determined after samples dissolution in H PO in the presence of a titrated solution of NFI VO, which excess was titrated with the Fe(II) salt. It was found that dissolution of the materials based on CeF CeFj in H PO does not change the oxidation state of cerium, thus phosphate complexes of Ce(III, IV) can be used for quantitative spectrophotometric determination of cerium valence forms. The contents of Ln(II, III) in Ln S LnS may be counted from results of the determination of total sulfur (determined gravimetric ally in BaSO form) and sum of the reducers - S and Ln(II) (determined by iodometric method). [Pg.164]

The spectra of these ion pairs are largely different, which forms the basis of the determination method for the spectrophotometric determination of acidic impurities. [Pg.180]

SPECTROPHOTOMETRIC DETERMINATION OF RARE EARTH ELEMENTS IN MONO CRYSTALS AND STARTING LEAD MOLYBDATE RAW MATERIAL... [Pg.201]

SOLID-PHASE EXTRACTION ON SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION TRACE IONS IN WATER WITH l-(2-PYRIDILAZO)-2-NAPHTOL... [Pg.269]

FLOW INJECTION - SPECTROPHOTOMETRIC DETERMINATION OF SELECTED CEFALOSPORINES... [Pg.356]

SPECTROPHOTOMETRIC DETERMINATION OF HYDROXYUREA AS A COMPLEX WITH FERRIC CHLORIDE AFTER STABILIZATION BY FERROUS IONS... [Pg.379]

SPECTROPHOTOMETRIC DETERMINATION OF ATORVASTATIN AND FLUVASTATIN IN PHARMACEUTICAL PREPARATIONS AFTER DERIVATIZATION WITH 9-CHLOROMETHYLANTHRACENE... [Pg.388]

The use of change of the balanced composition of the mixture depending from the reductive-oxidative potential is shown on the example of coulometric determination of iodides and bromides and spectrophotometric determination of iodides in the presence of bromides at electrochemical oxidation. [Pg.421]

Phosphorus and Silicon in Waters, Effluents and Sludges [e.g. Phosphorus in Waters, Effluents and Sludges by Spectrophotometry-phosphomolybdenum blue method. Phosphorus in Waters and Acidic Digests by Spectrophotometry-phosphovanadomolybdate method. Ion Chromatographic Methods for the Determination of Phosphorus Compound, Pretreatment Methods for Phosphorus Determinations, Determination of silicon by Spectrophotometric Determination of Molybdate Reactive Silicon-1 -amino-2-naphthol-4, sulphonic acid (ANSA) or Metol reduction methods or ascorbic acid reduction method. Pretreatment Methods to Convert Other Eorms of Silicon to Soluble Molybdate Reactive Silicon, Determination of Phosphorus and Silicon Emission Spectrophotometry], 1992... [Pg.315]

Clearly the accurate measurement of the final (infinity time) instrument reading is necessary for the application of the preceding methods, as exemplified by Eq. (2-52) for the spectrophotometric determination of a first-order rate constant. It sometimes happens, however, that this final value cannot be accurately measured. Among the reasons for this inability to determine are the occurrence of a slow secondary reaction, the precipitation of a product, an unsteady instrumental baseline, or simply a reaction so slow that it is inconvenient to wait for its completion. Methods have been devised to allow the rate constant to be evaluated without a known value of in the process, of course, an estimate of A is also obtainable. [Pg.36]

Any impurities present in the solvents may aifect the cut-ofT value, and it is therefore essential to employ materials of the highest purity. Most major suppliers of laboratory chemicals offer products which have been specially purified and carefully tested to ensure that they are of the requisite standard for use in spectrophotometric determinations. Such chemicals are usually identified by a special name as for example the Spectrosol , materials supplied by BDH Ltd. In many cases, however, it suffices to subject the purest material available to spectrophotometric examination, and if there is no appreciable absorption over the spectral range required for the proposed determination, the solvent may be used otherwise careful purification will be needed.18... [Pg.675]

In any colorimetric determination the exact procedure will be governed partly by the particular instrument to be employed and partly by the nature of the substance which is being determined. There are nevertheless certain general principles which are universally applicable and these are also relevant to spectrophotometric determinations in general. [Pg.675]

Discussion. This section is concerned with the simultaneous spectrophotometric determination of two solutes in a solution. The absorbances are additive, provided there is no reaction between the two solutes. We may write ... [Pg.712]

SPECTROPHOTOMETRIC DETERMINATION OF THE pAT VALUE OF AN INDICATOR (THE ACID DISSOCIATION CONSTANT OF METHYL RED)... [Pg.718]

Z Marczenko, Separation and Spectrophotometric Determination of Elements, 2nd edn, Wiley, Chichester, 1986... [Pg.815]

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