REVIEW OF FUNDAMENTAL DEVELOPMENTS IN ANALYSIS
I I. I
I I I I
I
Light Absorption Spectrometry M. G. MELLON, Purdue University, lar'uyefte, ind. D. F. BOLTZ, Wayne Sfafe University, Iletroit, Mich.
T
voluminous literature related to light absorption spectrometry for the period from August 1955 to August 1957 has been reviewed for this digest. The appraisement of approximately 800 articles was necessary in attempting to select those developments which, in the judgment of the reviewers, warranted documentation. Undoubtedly, in endeavoring to be more selective, some commendable publications may have been omitted. The classification of subject matter under the headings of Chemistry, Physics, and Applications has been followed as in previous review (347, HE
$48). CHEMISTRY
Progress has been made in determining the structures of complexes exhibiting light absorption and in delineating the optimum conditions for the formation of stable and reproducible colored systems. The recent developments related to the chemistry of the colored systems have been reviewed under the categories of reactions, structures, reagents, and preliminary chemical treatments involving complexation and analytical separation. Reactions. A selected bibliography of the inorganic colorimetric reactions known t o exist prior t o 1952 has been published, with the elements listed according to atomic number (115). The reactions considered in this review are classified according to their application to the determination of metals, nonmetals, and organic substances. METALS. A study of the chromiumdiphenylcarbazide reaction showed that 3 moles of diphenylcarbazide react with 2 moles of chromiuni(V1) to form a chromium(111)-diphenylcarbazone complex which can also be formed by diphenylcarbazone reacting with either chromium(I1) or (111) (421). Magnetic susceptibility measurements (108) indicate that the reaction mechanism between chromate and diphenylcarbazide involves the diphenylcarbazide and chromium(II1) rather than chromium(I1). A study of conditions for the formation of the heteropoly blues from molybdophosphoric and molybdoarsenic acids showed hydrazine sulfate or ascorbic acid to be preferred reductants (648). The instability constant for the heter-
554
ANALYTICAL CHEMISTRY
opoly blue of phixphorus is 2.6 X The presence of bismuth(II1) permits the reduction of either molybdophosphoric or molybdoarsenic acid to the heteropoly blue a t room temperature when ascorbic tcid is the reductant (238). The ratio of molybdenum(V1) to molybdenum(V) in the heteropoly blue of phosphorw is 2 to 1 (15). A study of the reaction of hydrogen peroxide with the iron(I1) and cobalt(I1) chelonates of either (ethylenedinitri1o)tetraacetic acid or nitriloacetic acid in basic solution showed that the ironEDTA chelonate and the cobalt chelonates are relativdy stable in the presence of excess hyclrogen peroxide (86)The Jorissen rlmtion, in which salicylic acid and nitrite react with copper(11) to give a red chelonate, has been studied critically (662). The optimum conditions involvc: a p E o f 4.1 to 4.2, the use of 50 mg. of potassium nitrite, and heating for 1 houi- a t 80' C. when 0.2 to 15 p.p.m. of copFer is determined. The reaction of rhenium(VI1) with thiourea, thiosemicarbazide, or diphenylcarbazide gives a colored product in hydrochloric acid solution, if a reducing agent suzh as chlorostannous acid or titanous chloride is present (465). The colored product was ReO2(TU)&1 with thiourea. Hecause of the insolubility of the diphe iylthiourea derivative, the resulting complex can be dissolved in sodium hydroxide and determined colorimetrically by thi? classical thiocyanate method. Of t,he organic compounds reacting with germanium(] V), those having large molecules, such as the fluorone or cumarin derivative,l with two phenolic groups in ortho positions, are preferable (262). The reaction b >tween zirconium(1V) and Alizarin S gives lakes of different zirconium-Alizariji S ratios, depending upon pH (194). The reaction of thorium(1V) and morin gives a complex having a 1 to 2 thorium-morin ratio. Maximum color development requires careful control of pH, the presence of ethanol, a definite morin concentration, and a 30-minute I-eaction time (147). A study of the Linetics ot the reaction of 1,lO-phenanthi*oline with nickel(I1) led to the proposd of two mechanisms for the formation of mono-(1,lO-phenanthroline)-nickel(I?:) chelate (333).
A spectrophotometric study of the reactions of 2,6-bis(4-phenyl-2-pyridyl)4-phenylpyridine (Terosite) with copper(I), iron(II), and cobalt(I1) has shown that stable complexes are formed with iron(I1) and cobalt(I1). The respective molar absorptivities are 30,200 at 582 mp and 3120 at 529 mp (477). The mechanism of formation and dissociation of the tris-2,2'-bipyridineiron(II) complex depends upon pH (976). Intermediates were postulated in which 2,2'bipyridine behnved as a monodentate group. I n very acidic media the reagent behaved as a diacidic base. I n the formation of tris-2,2'-bipyridineruthenium(II), intermediates of mono- and bis-2,2'-bipyridine-ruthenium(II1) complexes were identified (568). The color reaction of iron(II1) with phenols proceeds through a red to violet to blue transition with the introduction of hydroxyl and methoxy (electron donor) groups into the phenol and upon acidification (284). The reverse color transition was noted upon introduction of nitro- and sulfonic (electron acceptor) groups and addition of a base. The entropy changes and partial molar entropies have been calculated for eight different iron(II1) phenolic complexes (4). It was found that the group attached to the side chain carbon was effective in determining complex stability. Stability is highest for the 0- group, then the N H t group, and least for the H, CHI, or OCHs groups. The absorption spectra and composition of the complexes formed by the reaction of o-nitrosopheno1 with a number of cations in acidic, neutral, and basic aqueous and petroleum ether solutions have been studied (490). From a spectrophotometric study of nitrophenols with various cations, it was concluded that a nitro group ortho to the phenolic group is essential for the formation of a complex (67). Iron(III), chromium(III), aluminum, copper(II), nickel(II), zinc, manganese(II), calcium, cadmium, and cobalt(I1) complexes were investigated. Lithium has been precipitated quantitatively as the phosphate in basic solution, followed by dissolution of the precipitate in hydrochloric acid and determination of the phosphate as a heteropoly blue (397). Beryllium has been determined by precipitating beryllium
ammonium phosphate in slightly acidic solution, dissolving the precipitate in nitric acid, and determining tlie phosphate as molybdophosphoric acid (516). After a preliminary oxidation of cerium(II1) to cerium(1V) with lead dioxide, an excess of a n iron(I1) solution was added to reduce tlie cerium(IV), and the excess iron(I1) was determined with 1,10-phenanthroline (178). An indirect colorimetric method for uranium is based upon the oxidation of uranium(1V) to uranium(V1) by iron(III), followed by colorinietric determination of iron(I1) using 1,lO-phenanthroline (839). NONMETALS.The reaction of iodine with water to give hydrated iodinium and iodide ions can be accelerated by addition of a mercury(I1) salt which removes the iodide ion (240). The hydrated iodinium ion is postulated as then reacting with o-tolidine to give a yellow color. Iodine reacts with many organic compounds such as pyridine, quinoline, diethylsulfide, dioxane. and butyl alcohol to form 1 to 1 molar complexes (489). The reaction involving the displacement of thiocyanate by chloride from mercuric thiocyanate has been studied as the basis of a colorimetric method for determining traces of chloride (230, 621). The displaced thiocyanate is determined as iron(II1)-thiocyanate complex. Iodide, bromide, cyanide, sulfide, thiosulfate, bromate, iodate, and nitrite also displace thiocyanate from the mercuric thiocyanate reagent (554). Another displacement reaction between slightly soluble bariuni chloroanilate and sulfate results in the liberation of chloroanilate which in acid form exhibits characteristic light absorptivity a t 530 mw (49). Traces of thiosulfate ion are converted t o thiocyanate ion in the presence of copper(I1) and cyanide ions (502) and tetrathionate and higher polythionates are converted to thiocyanate with cyanide in basic solutions (391); the thiocyanate is then determined as iron(II1)-thiocyanate complex. Hydroxylamine reacts Kith 8-quinolino1 in the presence of ethanol and sodium carbonate to form 5,s-quinolinequinone-5-(8-hydrosy-5- quinolylimide), which has a green color and permits the spectrophotometric determination of hydroxylamine (161). ORGAXICCOMPOUXDS.A study of the color reaction of p-dimethylaminobenzaldehyde and p-ureido acids revealed an equilibrium reaction involving the forniation of a Schiff-base hydrochloride (92). In studying the mechanism of this reaction, the extent of conversion of the amine to cationic form was determined spectrophotonietrically. The cationic form of the reagent reacts with the p-ureido acids to give a quinoid structure having a yellow color. The nature of the alkyl group in the p-ureido
acid and the acidity are critical variables in maintaining optimum sensitivity and reproducibility. An investigation of the color reaction of hexuronic acids with anthrone in concentrated sulfuric acid solutions showed that, unlike hexoses, methylpentoses, and pentoses which give fading bluegreen hues, hexuronic acids give a red hue which gradually increases in intensity (205). Although careful control of sulfuric acid concentration is important, equally reproducible color intensities were obtained with fresh and aged reagents. From a study of the color reactions of vanillin with aldehydes and ketoses in basic solution, it was found that especially good coloration resulted with aliphatic ketones. The coloration was ameliorated if the methyl group was adjacent to the ketone group (296). The reaction in which some organophosphorus compounds accelerate the oxidation of benzidine has been studied and a reaction mechanism postulated involving the formation of a peracid prior to the oxidation of the amine (160). Traces of anhydrides of phosphorus and carbon; acid chlorides of phosphorus, carbon, and sulfur; and phosphonoand phosphorofluoridates can be determined using this reaction. Kertes (267) has studied the nonspecific reaction of dipicrylamine with organic bases in solvents of lorn dielectric constant. Structures. This section summarizes many of tlie contributions which have been made in t h e study of metal chelates, with special attention directed to the determination of the formula of the structures responsible for characteristic light absorption. Attention is called to several papers dealing with the determination of formulas of complexes and the evaluation of instability constants of compleses, using spectrophoton~etricmethods. The advantage of using the moleratio method is that the stoichiometry of all the complexes can be studied (353). The mole-ratio method is particularly superior when high ratio complexes are being studied. The determination of successive formation constants by spectrophotometry has been thoroughly discussed (387). A spectrophotometric study of the iron(II1) complexes formed n-ith either salicylic acid or sodium disulfonated pyrocatechol (Tiron) showed that three successive complexes were formed with each reagent (568). With Tiron, the color of the complexes containing 1, 2, or 3 moles of the chelon were blue, violet, and red, respectively. Iron(II1) forms a 1 to 3 complex with cysteine in acidic solutioii which is blue and has low absorptivity (410). I n basic solution, a red complex having a 1 to 3 ratio and high absorptivity is formed. The iron nitroso-R salt com-
plexes were iound to contain 2 and 3 moles of reag3nt per mole of iron (403). The formation of ternary complexes of iron(III), thiocyanate, and either sulfate or halid3 ions has been indicated (SUO). Only the red, Fe(SCN)S, complex is extrsctable with organic reagents (287). The reaction of Alizarin S and molybdate gives ,a brownish red comples having a mole ratio of 1 to 1 and showing conformity to Beer's law (382). Chloroanilic acid and molybdenum(V1) form a 1 to 1 complex (579). Spectrophotometric :vidence indicates that the quinquivalent molybdenum thiocyanate complex has a molybdenum-thiocyanate ratio of 1 to 6 (271). Thorium forms a 1 to 1 complex with Alizarin S (&9), a 1 to 2 colloidal complex with naphthazarin (363),and a 1 to 4 complex with carmine red (130). 2-(pSulfophenylnzo) - 1,8 - dihydrosy - 3,6 naphthalenedisulfonic acid (SPADNS) forms a blue-violet, 1 to 1 complex with thorium(1V) (9Q),and a pink, 1 to 1 complex rvit h zirconiuni(1V) (30). I n 21V1 perchloric acid, both flavanol and myricetin fcrm chelonates with zirconium having zirconium-reagent ratios of 1 to 1and 1 l o 2 (917). Uranium('q1) forms a stable complex with morelli n having a uranyl-niorellin ratio of 1 to 2, which is suitable for the estimation of uranium (436). p H affects the composition of the compound obtained when uranyl ion reacts with dihydroxyni:tleic acid (218). Complexes with uranium-reagent ratios of 1 to 1 and 2 to 1 are obtained a t pH of 3 and 6.8, respectively. The ratio of uranyl-Alizarin Red R is 1 to 1and the complex is s a b l e a t pH 8.2 (561). Vanadium (IV) and tungstophosphoric acid form a . to 1 complex having a purple hue (547). It has been suggest( 1 that the complex formed by the i n t x action of nickel, dimethylglyoxime, and a n oxidizing agent in basic solution consists of bi- cr tervalent nickel with partially oxidii ed dimethg-lglyoxime (20). 2,6-Bis(6- phenyl- 2- pyridyl) - 4-phenylpyridine foi-ms stable complexes with iron(I1) and cobalt(I1). The iron coniplex has a molar absorptivity of 30,200 (477). The instability constants of the mixed complexes of copper(I1) with ethylenedialnine, oxalate, acetylacetone, and dimethylglyoxime have been determined (960:l. Osmium(V1) forms a stable violet complex with l-naphthylainine-3,5,7trisulfonic :aid having a mole ratio of 1 to 2 (585). Aluminon with gallium(111) gives a complex with a metal-reagent ratio which is predominantly 1 to 1(443). The compounds fornied by the interaction of cations and aluminon were found to have metal-aluminon ratios of 2 to 1 for copper, 1 to 1 for aluminum, and 1 to 2 for iron (261). Aluminum and quinalizarin forin a 2 to 3 comVOL. 30, NO. 4, APRIL 1958
555
plex (8%’). Manganese(1V) forms a 1 to 4 complex with tellurate in basic Pyrocatechol, boric solution (644). acid, and pyridine form two complexes having ratios of 3: 1 :1 and 2: 1:1 (277). Reagents. The use of organic reagents in colorimetric analysis was discussed by J. H. Yoe in his Fisher Award Address (592). He outlined the steps in studying a color reaction involving a new organic reagent and the development of an analytical procedure. Reviews summarizing certain rules helpful in selecting an organic reagent and in predicting its analytical utility (207) and concerning analytical reagents containing the thiol and thiono groups (424) have been written. As the result of studies of titanium(IV) with different hydroxy oxo compounds, hydroxy acids, and aromatic dihydroxy compounds it mas concluded that the functional group for titanium should result in the formation of a chelate containing two oxygen atoms in a five- or six-membered ring (404). 7-Chloromethyl-8-quinolinol has been prepared and found to yield colored complexes or precipitates with a number of cations (141). Certain azo derivatives of 8-quinolinol gave characteristic colors with cations (581). 5-(2-Hydroxy - 3 - carboxyphenylazo) - 8-quinolinol gives a red-purple hue with silver, a purple hue with copper(II), and an orange hue with magnesium. 5-(2-Hydroxy - 5 - carboxyphenylazo) - 8 - quinolinol gives red-purple with cobalt(II), orange-red with nickel(II), and redorange with zinc. Numerous new reagents continue to be proposed for the determination of iron, the following being selected as most worthy of mention. Iron(II1) gives a red color with 5-sulfoanthranilic acid (698), a purple color with 2-fluorobenzok acid (69),an orange-red color with 8-Fesorcylic acid (564),a red-violet color with ethylenediamine-bis(sulfosalicyla1dehyde) (573), an orange color with paminosalicylic acid (574), a blue color with 4-amino-4methoxydiphenylamine (127), and a red color with thenoyltrifluoroacetone (264). Iron(I1) gives a green color with o-nitrosoresorcinol monomethyl ether (412, 645), and a purple color with 2,6-bis(4-phenyl-2pyridyl)-4-phenylpyridine (477). The platinum metals seem to have been given considerable attention recently, probably because of their use as catalysts. Iridium gives a purple color with o-dianisidine (46), a red color with p-nitrosodimethylaniline (677), and a purple color with leuco-crystal violet (17 ) . Osmium gives colored products extractable with chloroform with o,o’ditolylthiourea and C-diphenylthiosemicarbazide and ruthenium does likewise with 2,4-diphenylthiosemicarbazide and diphenylthiourea (165). 8-Diphenylthiourea has been recommended for de-
556
ANALYTICAL CHEMISTRY
termining ruthenium (268). 3-Hydroxy-1-p-sulfon dophenyl- 3 - phenyltriazine gives a yc:llow color with palladium(I1) (603). The preparatim of “alumocresone,” a reagent of the duminon type, and the colors it forms with iron(IIT), aluminum, beryllium, galliiun(III), uranyl, and chloroplatinate ions have been described (283). Gallic acid and tantalum(V) form a stable yel’ow complex (165). A new reagent for germanium is 2,6,7trihydroxy-9 - (4-dimethylaminophenyl) fluorone (261). Sulfosalicylic acid and aurintricarboxylic acid are recommended as the best reagents for the colorimetric determination of ions of the rare earths (219). Hematoxylin and hydrogen peroxide have been used in determining lanthanum and yttrium (465). 0-Mercaptopropionic acid, which produces a blue-green color with cobalt, has been used in colorimetric determination of cobalt (312). Mercaptosuccinic acid gives a yc4ow color with molybdate (80). The preparation of a-furilmonoxime and its use as a reagent in the determination of cobalt have been described (538). o-Nitrosoresorcinol monomethyl ether is a new reagent for cobalt which forms x red-orange complex (646). As only :his cobalt complex is extractable with carbon tetrachloride, iron and nickel do not interfere. Triethanolamine forms a green color with manganese(l1) (68); the method is less sensitive tharl the classical permanganate method. Magnesium forms a stable complex with 2- [2-hydroxy-3(2,4 - xylylcarbamoy1)-1 - naphthylazo] phenol (580). Rubeanic acid and trisodium pentacyanoamminoferritte are reported to be colorimetric reagents for many cations (209). Ammonium aurintricarboxylate has been studied as a colorimetric reagent for aluminum, beryllium, uranium, and thorium (376). Diphenylbenzidine has been used as a reagent for traces of vanadium (120). Pyrocatechol violet is a hii:hly sensitive reagent for zirconium (149. Pyrocatecholsul’onaphthalein gives a red color with lhorium, a blue color with bismuth in acidic solutions, and a blue color with copper(I1) a t p H 6.5 (618). Oxalyl dihydrazide has been used as a reagent for copper(I1) (184). Antimony(II1) gives a stable color with trihydroxyphenylf!uorone (583). Thorium(1V) forms a yellow complex with Arsenazo- [onitroso-R salt (2l7). (l,S-dihydroxy-3,6 .disulfo-2-naphthyl)benzenarsonic acic 1, has been used to determine zirconium colorimetrically (286). Gold(II1) has been determined using Rhodamine 1;(321). The complex formed by thallic m(II1) and Rhodamine B was extrac,;ed and served as the basis of a new ,,hotometric method (406). p-Phenetidine and thallium(II1)
form a red-violet complex (226). Salicylamidoxime and uranium(V1) react in basic solution to give a stable orangeyellow complex (27). I n glacial acetic acid, a,p,~, A-tetraphenylporphine forms a complex with zinc (31). N,N-Diethylnicotinamide and decaborane give an orange-red color suitable for colorimetric determination of decaborane (211). Resorcinol and iron(111) give a brown color, whose intensity is proportional to nitrous acid concentration (290). The blue color obtained with Variamine Blue (4-amino-4methoxydiphenylaniine) and iodine has been used as basis of a sensitive colorimetric method for iodine (128). Diaminochrysadn, diaminoanthrarufin, and tribromoanthrarufin are new reagents reported to give sensitive color reactions with borate in concentrated sulfuric acid solutions (93). These reagents are more sensitive than quinalizarin. Two new colorimetric reagents for determining traces of boron are 5benzamido-6-chloro- 1,l-bis(anthraquinony1)amine and 5-p-toluidine-1,l’-(anthraquinony1)amine (190). The properties of 3,3‘-diaminobenzidine as a reagent for selenium(1V) have been investigated (84). The preparation of a linear starch solution for use as a colorimetric reagent has been described (287). 4-(4-Nitrobenzyl)pyridine has been used in determining ION concentrations of ethylenimines and alkylating agents -e.g., diethyl sulfate and alkyl halides (126). Pyridine forms colored Schiff bases with 2,4-dichloro-6(o-chloroani1ino)-s-triazine and related compounds (70). An investigation of the anthrone reagent for carbohydrates showed that oxidation of the anthrone to dianthrone and nitration of the dianthrone, if the sample was contaminated with nitrate, resulted in darkening of the reagent (602). The use of pure sulfuric acid, the addition of thiourea, and the storage of the reagent a t low temperature are recommended to retard the darkening process. Molybdoarsenic acid, under controlled conditions, is a highly specific reagent for 5-keto-~-gluconic acid (417). 1Methyl-1-phenylhydrazine sulfate has also been reported as being specific for the 5-ketogluconate in the presence of the 2-ketogluconate (480). Molybdosilicic acid is a highly specific reagent for aliphatic aldehydes having hydrogen on the alpha-carbon atom (60). A heteropoly blue is presumably produced. Reagents based on the heteropoly derivatives of molybdate and tungstate have been studied (665). A specificity of 1naphthol for the cupribromide reagent in the presence of other phenolics has been observed (466). Preliminary Treatments. Often before colorimetric comparisons or spectrophotometric measurements can b e
made, it is necessary t o perform certain preliminary chemical treatments t o ensure reliability. Several examples of two types of such preliminary chemical treatment follow. PROTECTIVE R E ~ C T I O N S . The use of a sulfuric acid, nitric acid, and selenium mixture and, if necessary, a perchloric and nitric acid mixture to dissolve organic phosphorus compounds prior to the colorimetric determination of phosphorus has been outlined (109). The thermal decomposition of fluorinated organic compounds in the gas phase using a quartz tube is suggested in order to form silicon tetrafluoride, which can then be recovered in water and the heteropoly blue method for silicon utilized (414). Trace amounts of free chlorine were concentrated by extracting with chloroform and then adding sodium hydroxide to form hypochlorite, which transferred to the aqueous phase (281). I n storing sea water samples for the determination of dissolved inorganic phosphate, chloroform is added to inhibit bacterial action; the use of polyethylene bottles is not recommended because of phosphate adsorption (379). Oxidation to antimony(V) with perchloric acid and the addition of hydrogen peroxide to form peroxy complexes of molybdenum and niobium prevented these elements from interfering in the colorimetric determination of germanium with phenylfluorone (309). A small amount of sodium azide destroys nitrites prior to colorimetric determination of nitrate (216). Fluoride complexes interfering cations in the determination of cobalt with nitroso-R salt; the addition of niagnesium acetate is recommended t o decrease the danger of etching the cells (@@. Interference of zirconium can be circumvented by using a tartaric acid system in determining thorium with Thoron (189). Iron(II1) can be coniplexed with phosphoric acid in determining chromium in copper alloys using diphenylcarbazide (867). I n determining magnesium with titan yellow, the interference caused by manganese(11), copper(II), iron(III), and aluminum can be prevented by adding potassium cyanide and hydroxylamine (73).
(Ethylenedinitri1o)tetraacetate
(E-
DTA) has been used to advantage in complexing interfering cations as exemplified in the following determinations: bismuth in rocks with diethyldithiocarbamate (671); titanium in steel with hydrogen peroxide (422); and beryllium in alloys with $-@nitropheny1azo)orcinol (98). SEPARATIONS.The necessity of separating trace amounts of desired constituent from relatively large amounts of interfering substances continues to deserve the attention of analysts. Be-
cause of certain inherent advantages of liquid-liquid extraction, this method is becoming a more popular adjunct to colorimetry. A timely new book, "Solvent Extraction in Analytical Chemistry" by Morrison and Freiser, contains much vaIuable information on the separation or isolation of specific inorganic constituents (3669). Representative analytical separations are summarized in Table I. Several developments of special interest follow. The separation of zirconium from fission products and metal ions by use of 2-thenoyltrifluoroacetone and xylene as a highly selective extractant for the zirconium chelate has been studied critically (366). The extraction of uranium(V1) with 8-quinolinol and its derivatives showed that the optimum p H ranges for the extraction with chloroform were 5.8 to 8, 5.4 to 7.2, and 5.6 to 7.3, respectively, for the complexes formed with 8-quinolinol, 5,7-dichloro-
&quinolinol, rtnd 5,7-dibrom0-8-quinolinol (464). Alkyl benzenesulfonates are quantitatively extracted by chloroform as a coinplex of l-methylheptylamine, which makes possible a separation from inorganic salts and soluble organic material (459). The separaiion of zinc and cadmium as negatively charged chloro complexes from other critions by anion exchange and the partitioning of the zinc and cadmium by ising a sodium hydroxide solution as e.utriant for the zinc and then nitric acid as elutriant for cadmium is a good example of the versatility of the ion exchringe method of effecting analytical separations (250). The scparation of morphine from extracts of poppy plant,s by ion exchange, prior to the colorimetric determination, is another interesting example (567). First, a cation exchanger, in hydrogen form, was used; the discardable effluent contained anions and neitral substances. Elution
Table I. Analytical Separations of Inorganic Constituents Desired Constituent Constituent Separated Reagent Method Ref. As As Diethyl xanthate, carbon E:ctraction (613) tetrachloride B Ti Hydrogen peroxide, cat,ion Icn exchange (78) exchangeresin B B(F -)a Diethyl ether Extraction (449) Ba, Sr, Ca, Ba, Sr, Ca, Paper Chromatography (487) Ir lug
Mg
co CS F F F
Fe Ga Ge Ge Ge Ir Li
Ethyl xanthate Cation exchange resin Cat,ion exchange Anion exchange
Fe Ga(Fe)a
Ferron, amyl alcohol Extraction Isopropyl ether, titanium(I1) Extraction ZrOC12 Precipitation ... 0 istillation Silica carrier Precipitation Cation exchange resin Ion exchange Isobutyl alcohol Extraction
PO4-0
% % hlo hlo
N3Ni NO1 NO,P04-'
-
POI-' PO, -'
Re Se Sn
co Cs(Rb, Na)O Cr f3 FSiF,
E~traction Icn exchange Im exchange Ion exchange Distillation
...
GeClr Ge Ni LiCl(NaC1, KC1)a AI, Cu, Fe, 8-Quinolinol, chloroform Mn, Ni c-I1 .. Sulfuric acid, methanol cu Dithizone, chloroform Mo(Cu, Fe, Paper Co, U, Cr, Ni, hfn)4, Mo Hexone (4-methyl-2-pentanone) "3
Fe c1-
vs P(As)* Hap04 (Si0,-2). Mo Th Cu, Bi, Hg
Ethyl xanthate Iodate Diethyldithiocarbamate, chloroform Hydrogen bromide Cyclohexanone
(810)
(97)
(104 $20, L71 I
Extraction Precipitation Extraction Chromatography Extraction 1)istillntion Extraction Precipitation Ion exchange F recipitation Extraction Ektraction Ektraction I'rccipitation Extraction
IXstillation Extraction 2-Thenoyltrifluoroacetone in Kxtraction benzene Anion exchange resin U(Fe, V)* Ion exchange U U Cupferron and ether Extraction V I 'r e cipitation Cr Phosphoric acid, sodium tungstate Parentheses indicate principal diverse element@). Sn Th
Sn Th(N0a)r
Isopropyl etdeP Silver sulfate Cation exchange Cupferron Amyl alcohol Molybdate, isobutyl alcohol
(425)
(44.2)
VOL. 30, NO. 4, APRIL 1958
557
of this column with ammonium hydroxide gave a n eluate containing bases, cations, and ampholytes. This eluate was passed through a n anion exchange column, in hydroxyl form, t o give another discardable efluent containing the cations and bases. Elution of this anion column with acetic acid resulted i n an eluate containing the ampholytes. This second eluate was added to the top of a third column consisting of a cation exchanger, in sodium form. After elution with an elutriant of p H 8.6 to remove the discardable ampholytes, the eluate containing morphine was collected by eluting wibh a buffer solution of p H 9.4. PHYSICS
The physical aspects underlying the nieasureinent of light absorption are considered under the following headings: principles of light absorption measurements, and instrumentation. Principles of Light Absorption Measurements. T h e theory of light absorption by complex compounds has been discussed thoroughly (266). A derivation of the Beer-Bouguer law based on the combination of proportional dependences has been presented (220). The applications and the errors of differential colorinietric and spectrophotometric methods have been discussed (525). The principles of differential spectrophotometry and corrections to eliminate errors when unmatched cuvettes are used have been reviewed (152). Three methods of correcting for differences in cell length in precision colorimetry have been presented (32). The calculation in a simultaneous spectrophotometric analysis of a binary system can be simplified by plotting the ratios of the absorbance a t a selected wave length t o the absorbance at the isosbestic point wave length against the mole per cent composition (60). The precision of indirect spectrophotometry can be increased by using a partially decolorized reference solution instead of a completely bleached solution ($02). The theoretical basis of a method for calculating photometric end points in titrations for photonietric titration graphs which exhibit extensive curvature in the proximity of the equivalence point has been discussed (192). A collaborative study of alkaline potassium chromate solutions using Cary Model 10 spectrophotometers showed good agreement in the central part of the absorbance scale (556). AIedian niolar absorptivity values obtained for a solution containing 0.0400 gram of potassium chromate per liter of 0.05S potassium hydroxide solution were 3790 at 273 m p and 4820 at 373 m p , in good agreement with previous literature values. 558
ANALYTICAL CHEMISTRY
Constituent AI
Material
Elag
... .., ...
&ass 7 ‘itanium Corrosion products PJloys
E tee1 Iron ore Copper alloys ]Crater Calcium Steel Au Be
Ilronze Titanium alloys PJuminum alloys Ileryl Clres, alloys
... ...
Ba
Bi
Frotein
Icad
...
...
Loclrs Copper
... ...
Ca Cd
Alloys
...
Plater Ce co
... Ore
S ;eel
Alloys
S,eel S;eel Ores Si,eel Cr
... ... ... ...
Alloys
... C 3pper alloys Chromite cu
TItanium
... ... ...
B ological Steel Solder OIW Molybdenum products Fuel oil Plants Steel
LEad Aluminum alloys
Table 11. Method or Reagent Arsenazo Quinalizarin 8-Quinolinol Stilbazo Eriochrome Cyanine R Aluminon Aluminon 8-Hydroxyquinaldine-chloroform
8-Qiiiilinol Eriochrome Cyanine R Eriochrome Cyanine R 8-Quinolinol 8-Quinolinol Aurintricarboxylate Rhodamine B Ascorbic acid Toron
4-( p-Kitropheny1azo)orcinal
Toron
( p-Kitropheny1azo)orcinal
Molybdophosphoric acid Eriochrome Cyanine R
(p-Kitropheny1azo)oreinal
EDTA o-Cresolphthalein complexon Turbidimetric Pyrocatecholsulfonaphthalein
Thiourea Diethyldithiocnrbamatechloroform Iodide Murexide o-Cresolphthalein complexon Dithizone-carbon tetrachloride 4-Hydroxy-3-nitrophenyl-
arsonic acid Thiosinamine-diff erential 1,IO-Phenanthroline Ethyl xanthate-carbon tetrachloride 2-Nitroso-I-naphthol-chloroform Nitroso-R salt Kitroso-R salt Nitrosoresorcinol monomethyl ether 1-Furilmonoxime 2-hIercaptopropionic acid Diethylenetriamine Potassium ferricyanide 2-Nitroso-1-na~hthol Nitroso-R salt’ Nitroso-R salt Tributyl ammonium thiocyanate and amyl alcohol (Ethylenedinitri1o)tetraacetic acid
o-Aminophenyldithiocarbaniic
acid Diphenylcarbaxide Trilon B Salicylic acid-nitrite Neocuproine Oxalyldihydrazide ATeocuproine Die thyldithiocarbamate 2,2’-Biquinoline Neocuproine Tetraethylthiuram disulfide a-Benxoinoxime Neocuproine Dibenayldithiocarbainate
Biscvclohexanone oxalyldihydrazone Diethylammonium diethyldithiocarbamate Salicylaldoxime
Photometric Ref.
Methods for Metals Constituent
cu
Method or Reagent Rubeanic acid, turbidimetric Sodium diethyldithiocarbam-
Material Alloys Steel
n.te
N Giuproine 2,2 ‘-Biquinoline Heteropoly blue 2-Fluorobenzoic acid 2-Resorcyclic acid 5-Sulfoanthranilic acid S-Hydroxyquinaldine Terosite Salicylaldehydeglycine hydroxamic acid Diphenylthiovioluric acid Nitrosoresorcinol monomethyl ether p-Aminosalicylic acid Ethylenediamine-bis( sulfosalicylaldehyde) Thiocvanate 4,7-Dihydr oxy-1,1O-phenanthroline 2,2’-Bipyridine 1,lO-Phenanthroline 2,2’-Bipyridine Sulfosalicylic acid 2-Furyldian tipyrinylmethanc thiocyanate 1,lO-Phenanthroline 2,2’-Bipyridine 8-Quinolinol-chloroform Rhodamine B Aluminon Phenylfluorone
Tungsten ilcrylnitrite
...
Cs Fe
... ... ... ... ...
... ...
Alloys Glass sand Metal Acrylnitrile Nickel Copper alloys Water
Ga
Calcium Phosphates Germanium ...
... ...
Ge
... ...
Quercetin Nolybdovanadogermanic acid Ileteropoly blue 2,Ci17-Trihydroxy-9-(4 4 methylaminopheny1)fluorone Phenvlfluorone Phenjrlfluorone 8-Quinolinol-chloroform Chlorostannous acid-hydrobromic acid Leuco-crystal violet o-Dianisidine p-Xi trosodimethylaniline
... ...
In Ir
Zinc concentrate Ammonia Germanium ,.
.. ..
(Ethylenedinitri1o)tetraacetic
La
...
Li
...
acid Hematoxylin-hydrogen oxide Thoron Heteropoly blue Titan yellow
... ... ...
bIg
per-
Sodium-l-axo-2-hydroxy-3(2,4-dimethyIcarboxyanil-
idoha~hthalene-142-hvdroxy6enzene-5-sulronite)
...
2- [2-Hydroxy-3-(2,4-xylyl-
carbamoyl)-1-naphthylazo]
... Kickel rllkali products A h
Mo
Ores
Calcium
...
.4luminum alloys ... ... ... Soils Soils Alloys Steel
phenol Eriochrome Black T 8-Quinolinol Thiazole yellow Permanganate Permanganate Tellurate Triethanolamine Mercaptoacetic acid Thiocyanate rllizarin S Dithiolisoamgl acetate Toluene-3,4-dithiol Peroxide Th iocynnate
(Continued on page 660)
-
In discussing fluorescence effects in spectrophotonietry, it has been pointed out that the amount of stray light reaching the photovell should increase as the distance b e t w e n the photocell and solution increases iiid that nonconformity of the Beer-Bousuer law at high absorbance values for some organic compounds is not instrumental in nature (63). A method of measuring the light absorption and the index of refraction of high absorbance solutions utilizing a minute amount of solution, a planeconvex lens type of cumtte, and a microscope has been described (620). By reducing the ratio of volume of reagents added after decantation to the total volume of solution, precise results were obtained for certain colorimetric determinations wh3n decantations were used instead of volumetric transfers (174). Conditions affecting, and means of obtaining, ac curate measurements in constant-flow applications have been discussed (1C0,396). Factors related to the effect of scattered radiant energy on absorbance have been discussed in reference t o :Lsuspension of blood corpuscles (804‘1. Equations have been derived relating the absorbance of a suspension of absorbing particles to the absorbance 0 ’ the same total absorbing material in triie solution (116). By taking the first derivative of transmittance in rwpect to nave length, it is possible to detect low intensity bands overlapped b,y bands of higher intensity (166). A m:thod of presenting spectrophotometric data on the screen of an oscillograph and obtaining a permanent record by phc tography has been outlined (54). Instrumentation. Recording attachments and atxessory units continue t o command af tention, with apparently more interest being directed t o monitoring devices. Sommer (604) reported on new phot ,emissive cathodes of high sensitivity. Visible responsive cathodes of the mtimony-alkali metal type are greatly iniproved in respect to quant u m efficiency and threshold wave Iength if more than one alkali metal was present. Ur like single alkali cathodes, these multi-ttlkali cathodes decrease in sensitivity with oxygen uptake. SPECTROPHOTOMETERS. A recording microspectrophotometer, incorporating a n optical attenuator in the reference beam, is suitable for obtaining visible and ultraviolet absorption spectra using as little as 0 1 nil. (570). The Unicam S.P. 600 spectrophotometer has been described anll compared with the Hilger Spekker absorptiometer in respect t o applications in the metallurgical industry (103,l. The stability and sensitivity are satisfactory in a Unicam S.P. 500 spectrophotometer, when a bridge voltage regulator is used to convert to alternating current line operation (870). VOL. 30, NO. 4, APRIL 1958
559
A double monochromator with diffraction gratings has been described ($66). An attachment which converts any good monochromator to a doublebeam system, permitting the recording of the logarithm of transmittance, has been developed (201). This unit employs a rotating sector, a logarithmic response amplifier with negative feedback for gain control, and a multiplying phototube operated a t constant anode current. Attachments which convert a spectrograph t o a rapid response spectrophotometer ( I l l ) , and to a visual spectrophotometer (366), have been designed. Golay (173) discussed a ratio-measuring spectrophotometric system which utilizes the principle of measuring the electrical phase angle between a detector signal and the reference signal. Descriptions of the electrical system and three optical systems constructed on this principle were given. Although a specific application to infrared absorption was cited, the underlying principle and the fact that the direct current output is directly recordable are noteworthy for this review. Modifications of the Beckman DU spectrophotometer include devices for conversion to direct reading recording (76, 134); a new high pressure mercury arc source and a multiplying photodetector for measurements to 192 mp (636); and a new power supply which eliminates dry cells, the storage battery, and the ultraviolet accessory power supply (39). An integrating sphere for total reflectance measurements to be used with a Beckman DR recording spectrophotometer has been designed (231). A plastic sheet with a n inscribed wave length scale facilitates assignment of wave lengths for spectra obtained with a Beckman DK-1 spectrophotometer (297). FILTER PHOTOMETERS. A photometer which uses 100-mm. capillary cells is applicable to trace analysis (177). A lightweight, portable photoelectric absorptiometer is sensitive to 0.8 y of chromium, 0.3 y of manganese, and 0.3-7 of phosphorus (660). A new filter photometer, Model 834, has been announced by ITeston Electrical Instrument Corp. (679). The Hach direct reading electric colorimeter has 27 direct reading scales for water and sewage analysis (196). The reproducibility obtainable with a doublebeam electrophotometer was improved by using a device to integrate the photocurrent for a certain time interval (380).
Constituent Mo
Material So%water C mcentratee Silicate rocks Si eel A Uoy
...
Na Nb
...
... ... ...
Nd Ni
Steel 01.e Steel N 3-Y mixture Copper alloys Ciilcium CItt alysts Copper orcg
... ... ...
...
OS Pd
... ... ...
... ... ...
Pt Catalysts RO Rare earths Rh Ru
Sb
... ... ... ... ... ... ...
sc
Sol der Germanium Urmium waste prod-
Sm Sn
Ce-ite eartha Br:iss
11cts
alloy^
Silicates
Sr
T& Ort! Steel
...
...
mosphere samples by measuring the red color developed OIL a cloth tape impregnated with triphen yltetrazolium chloride (278). A portabls instrument for determining dissolvod oxygen in water, using leucoindigo-carmine, involves comparison with stardards (19). A continuous analyzer determines trace SPECIFIC APPLICATION INSTRUMENTS. amounts of oxyger. in gases ($65), and a A device provides for continuous or special automatic meter determines manual monitoring of the absorbance residual silica in water by the heterof chromatographic column eluates opoly blue method (481). An apparatus for studying fast re(607). A differential reflectance photomactions employs s cathode-ray tube. eter monitors automatically the boron The spectrum is recorded on photohydride concentration in metered at-
560
0
ANALYTICAL CHEMISTRY
Table II. Photometric Ref. Method or Reagent Toluene-3,C-dithiol Thiocyanate a-Benzoin Phenylhydrazine Chloroanilic acid Zinc uranylacetate-thiocyanate (274) (378) Thiocyanate Peroxide Pyrogallol Tiron Thiocyanate Pyrocatechol Pyrogallol Differential Dimethylglyoxime-chloroform Dimethylglyoxjme-chloroform Dimethylglgoxime Hypobromite-dimethylglyoxime Diethylenetriamine Dimethylglyoxime a-Furildioxime lJ4-Dlphenylthiosemicarbazide Rubeanic acid a-Furildioxime 3-Hydroxy-1-p-sulfonatophenyl-3-phenyltriazine I-Nitroso-2-naphtho1, turbidimetric Chlorostannous acid Chlorost,annous acid, simultaneous Chlorostannous acid a-Furildioxime 2,4-Diphenylthiosemicarbazide Monochromatic Chlorostannous acid o,o’-Ditolylthiourea s-Diphenylthiourea Phenylfluorone Molsbdovanadosilicic acid Rhidamine B Methyl violet Alizarin Red S Monochromatic Quercetin Phenylfluorene Dithiol o-Cresolphthalein complexon Pyrqgallol Gallic acid Pyrocatechol Pyrogallol
graphic paper mounted on a rapidly rotating drum (77). Automatic analyzers have been used to monitor the uranium content in process streams by measuring the light absorptive capacity of the uranium thiocyanate complex a t 365 mp (61). A photometer measures the reflected light from paper chromatograms (139). A whole blood colorimeter continuously registers the concentration of Evans blue dye (138). Hunter described two photoelectric tristimulus colorimetera which gave direct readings of luminance and chromaticity for the colors of tele-
Methods for Metals (Continued from page 559) Constituent Material Method or Reagent Th ... Alizarin S ... 2-( o-Arsenopheny1azo)chomotropic acid ... Morellin ... 1-(o-Arsenophenylazo)-2-naphthol-3,6-disulfonic acid ... Nitroso-R salt ... Naphthalazarin ... Carmine red Thoron Monazite sands Morin Urine Cerite earths SPADNS Ti Steel Peroxide Uranium Peroxide Uranyl nitrate Thymol ... %&uinolinol Complexon I11 Polyet hyle‘de Peroxide T1 ... p-Aminophenol ... p-Phenetidine ... Rhodamine B Brilliant Green-amyl acetate U blorellin Sulfuric acid ... Thiocyanate-methyl isobutyl ketone ... 1, IO-Phenanthroline ... Sulfateaifferential ... hlorin ... Perchloric acid-differential ... Salicylamidoxime Azide ... Ore Hydrogen peroxide Monazite concentrates Thioeyanate Diff erential-azide Alloys V Thiocyanate, acetone ... Hematoxylin, hydrogen per...
... ... ...
trophotometer (161, 245). A special cell in which solid samples such a s semiconductclrs can be immersed in gaseous helium and repositioned a t the operating temperature has been developed (44;). Additional accessories are a n adapter which fits inside the cell (187), a short light path cell (660) for very small volumes-e.g., 0.2 t o 1.0 m1.-a thermostated cell holder for the Unicam S.P. 500 spectrophotometer (186), and a n adapter for the Cary spectIophotometer cell holder for potassium bromide pellets (587). A special high temperature cell holder and special cells modify the Beckman D U spectrophotometer so that i t can be used to determine the absorption spectra of molten salts u p to a tempei*ature of 650” C. (616). A multiple-thickness cell is useful in changing the light path instead of varying the concentration (649). A special flow cell with centrifugal pump serves for spectrophotometric titrations using the Beckmar Model B (293). APPLICATIONS
I
Aluminum alloys Steel Steels, oils
W
Iron sand Organic Steel Brine Metals Silicates ’ Sea water
... ..*
Zn Zr
1 . .
Minerals
Steel
Thorium Steel
vision picture tubes (228). An automatic recording color densitometer has been described (636). A photoelectric photometer, PH-200, will accommodate any commercially available phototube (1.21); the meter reads in per cent transmittance, 0 to loo%, and in absorbance, 0 to 2. An apparatus for spectrophotometric titrations, which produces a voltage signal proportional to the third derivative of the photometer output, automatically terminates the titration (326). A logarithmic attenuator circuit and a titrant delivery system, which permits the automatic recording of ab-
PE hexanol Diphenylamine sulfonate Tungstovanadophosphoric acid Hydrogen peroxide Diphenylaminesulfonate Dithiol-amyl acetate a-Benzoin Toluene-3,4dithiol CY,@, y,A-Tetraphenylporphme Alizarin Red S-differential Pyrocatechol violet Arsenazo Alizarin S SPADNS Alizarin S Chloranilic acid Alizarin Red S Alizarin Red S
sorbance with a Beckman Model B spectrophotometer, have been utilized in automatic Photometric iodometric and acidimetric titrations (33.4). ABSORPTION CELLS. A compact fourchannel, thermostated stop-flow mixing device and absorption cell, designed for use with the Beckman DU spectrophotometer, enables reactions with half lives of 1 to 60 seconds to be studied (41). A constant temperature cell is adaptable to the continuous study of equilibrium or reaction kinetics (171). Several absorption cells are for lowtemperature work with the Cary spec-
This part of the review is concerned with the application of light absorption spectrometrj to practical problems in chemical an tlysis and color specification. New inethods, modified classical methods, iriproved techniques, and better instrumentation hai7e resulted in many interesting developments. Most of these applications have been summarized in Tables 11,111,and IV. Attention is directed to several publications deTroted entirely, or in part, to spectrop iotometric analysis. The “1956 Book of ASThl hfethods for the Chemical Analysis of hfetals” contains new and revised photometric methods (6). ‘?Metallurgical Analysis” (2W), “Kolorimetr sche Analyse” (288),“Analisi Fotome1,ria” (76), and “Kolorimetrie” (3%;) are foreign publications. Interscience has announced “CoIorimetric Detc rmination of Nonmetals” (69). An “Ultraviolet and Visible Absorption Spectra Index for 193054” has been published (208). Permanent Standards. For certain routine determinations the practice of using perrianent color standards seems t o persist. Solutions of pcarotene in mineral oil have been found stable, for 9 months and suitable for referenc? for the determination of carotene (4%). Potassium chromate solutions have been used as reference standards in the determinations of bismuth by the iodide method (37‘). Simultamous Spectrophotometric Determinations. T h e simultaneous photometric: determination of molybdenum and tungsten as the a-benzoin complexes has been applied t o silicate rock analyss (239). Copper and iron are determ ned simultaneously using VOL. 30,, NO. 4, APRIL 1958
561
the iron(I1)-bathoplienanthroline complex and the copper(1)-neocuproine complex (595). It is also possible to extract the copper complex with isopentyl alcohol and make successive determinations using the alcohol and aqueous phases. A method for the simultaneous determination of rhodiuni and platinum was developed using tin(I1) chloride as a reagent (18). Nickel(I1) and cobalt(I1) form violet and yellow complexes, respectively, with excess diethylenetriamine which serve as the basis of a simultaneous determination of these two elements (680). The simultaneous determination of cobalt and iron is possible using “terosite” as a reagent (477). The simultaneous determination of traces of benzene and toluene is possible following nitration (199). Vitamins Dz and DS in pure solution can be estimated by simultaneous spectrophotometry following treatment with furfural and sulfuric acid (291). Ninhydrin is the reagent used in determining pipecolic acid a n d proline (496). * Photometric Titrations. AIeasureinent of the light-absorptive property of t h e titrant or indicator serves as a sensitive method of detecting the equivalence point in titrimetry. Small aniounts of barium can be titrated with 0.01 to 0.0021W (cthylenedinitri1o)tetraacetate solutions using either phthalein purple (94) or Eriochrome Black-T (451) as indicators. The photometric titration of cerium(II1) with permanganate in neutral pyrophosphate solution has been studied ($36). Iron has been titrated with electrically generated titanium(II1) using leucomethylene blue as indicator ($27). Titanium can be determined by reducing to titanium(II1) with a cadmium reductor, adding a n excess of iron(II1) solution, and then titrating the excess iron(II1) with electrically generated titanium(II1) (328). Fluoride has been titrated with thorium nitrate using Alizarin Red S as indicator and photometric detection (293, 313). Color Specification. The relationship between the maximum instrument error in the spectrophotometric measurements of colored samples and the corresponding maximum displacement of t h e C I E chromaticity coordinates has been described and equations have been derived to compute these quantitative relationships (315, 491). Digital computers are used in applying the Adams-Nickerson equation to the calculation of CIE coordinates of color tolerance ellipsoids (408). Analytical approximations for colorimetric coeffirients based on least-squares analysis showed discrepancies exceeding the probable errors of the experimental determinations (314). The propagation of errors in tristiniulus colorimetry has been further considered by Kimeroff (393). Projective transformations of 562
ANALYTICAL CHEMISTRY
Table Ill. Photometric Constituent A3
B
R1 aterial Sulfur Steel Steel Gold Copper alloys Water Steel Germanium Fluorido salts Titaniui 11 Water
... ...
BiaHir Br
c Clz CI -
ClO -
co
Cast iron Water Water
,..
... ...
Water Chlorin ited lime Air
...
F-
Hn HNO? HzOr HzS I? li
... ... Plating baths Organic compounds Water Feed Gases
... ... Air Stecl
... ...
N3 -
KH3
KO, -
NO KO2
...
... Water Sea watjr Water Water Air Air
...
... ...
Method or Reagent Heteropoly blue Colloidal-n ephelometric Heteropoly blue Heteropoly blue Heteropoly blue Heteropoly blue Heteropoly blue Heteropoly blue Carminic acid Carminic acid Carminie acid Quinalizarin N,N-Die thylnico tinamide Tetrachromofluoroscein Mixed acid Indophenolate Tetramethylbeneidine Iron(II1) perchlorate Iron( 111)thiocyanate Mercury( 11)thiocyanate Mercury(I1) thiocyanate Indophenolate Iodine pentoxide Silver-p-sulfamoylbenzoic acid Thorium-Alizarin Red S, differential Thorium-Alizarin Red S Aluminum-Chromeazurol Aluminum-Eriochrome Cyanine Aluminon Heteropoly blue Heteropoly blue Titanium-ascorbic acid Methylene blue-palladium(I1) Resorcinol, iron(I1) chloride Titanium(IV) Methylene blue Variamine blue Pyridine-pyrazolone Iron(II1) azide Hypochlorite-phenate Nessler Xylenol Sulfanilic acid and 1-naphthylamine Salicylate-trichloroacetic acid Phenarsazinic acid Iron(I1) sulfate Strychnidine Griess Griess Procaine Rivanol
the CIE chromalicity diagram by a graphical method is discussed for various types of proje2tive transformations (588). A comparison of the successive, or memory, color matching method with the simultaneous, or juxtaposed, color matching method showed the first to be more rapid bull subject to a higher variability in rcplicative matchings (386). Glass color standards have been developed to match the chromaticities of the previous officirJ color standards for the various design:itions of maple sirup (64). A color comparator for grading rnaple sirup was a1 3 0 devised
Ref.
The influence of optical geometry and absorption coefficient on diffuse reflcctance values has been investigated and the fact that reflectometers of different geometries give very different reflectance values has been substantiated (509). I n a discussion of adranced color geometry, the concept of defining a non-Euclidean distance as a measure of the distance between two colors is suggested (567). The procedure for obtaining typical color curves for unknown powdered material by means of reflection measurements has been discussed (,273). An improved method of integrating the spectrophotometric curves obtained with a General Electric spectrophotom-
Methods for Nonmetals Constitueiit hlaterial
...
0 2
Gases Ethylene Water Beer
Water MTater P
so2
Organic Ore Soils Copper alloys Steel Vanadic acid Carbon steel Sea water Phospholipides Steel Boiler waters Uranium Petroleum products Organic compounds Biological Cast iron Fertilizers Plant materials Water Detergents Organic Organic and inorganic compounds Uranium Air
so1
Water
P
P30'0--*
S S -2
-2
... ..
S40.3-2
s*oa-2 se Si
.. Sulfur
... P . .
Cast iron' ' ' Steel
Si Te
Steel Water Thorium oxide Cathode nickel Uranium Calcium Steel
Method or Reagent Anthraquinone-2-sulfonate .4nthraquinone-2-sulfonate
Anthraquinone-2-sulfonate Winkler reagent Reduced indigo sulfonate JIanganese(I1) formaldehyde Reduced indigo carmine Heteropoly blue Jfolybdovanodophosphoricacid Heter opoly blue-thiourea Molybdovanadophosphoric acid JIolybdovanadophosphoric acid Heteropoly blue Heteropoly blue Heteropoly blue Molybdovanadophosphoric acid Modified heteropoly blue Heteropoly blue Heteropoly blue i\Iolybdovanadophosphoric acid Heteropoly blue Molybdovanadophosphoric acid Rlolybdovanadophosphoric acid Heteropoly blue Heteropoly blue Heteropoly blue Heteropoly blue hIolybdovanadophosphoric acid Heteropoly blue Tris(ethylenediamine)cobalt( III)l Methylene blue Methylene blue Karl Fischer Vanadate-silica gels Pararosaniline hydrochloride Barium chloroanilate Iron( 111) thiocyanate Iron(II1) thiocyanate Stannous chloride-sol 3,3'-Diaminobenzidine Molybdosilicic acid Heteropoly blue Heteropoly blue Heteropoly blue Molybdosilicic acid Molybdosilicic acid Heteropoly blue Heteropoly blue Molybdosilicic acid Heteropoly blue Diethyldithiocarbamate Hydrochloric acid
eter in order to obtain tristimulus values has been developed ( 5 ) . Approsimatelv 55 wavelength ordinates are used io determine the transmittance or reflectance values. which are then multiplied by appropriate factors. LITERATURE CITED
(1) Abelson, D., Bondy, P. K., ANAL. CHEM.28, 1922 (1956). (2) Adamoyich, L. P., Yutsis, B. V., Ukrazn. K h i m . Zhur. 22, 523 (1956). (3) Ibid., D. 805. (4) &ye< A, Svensk. Kem. l'idskr. 68, 189 (1956). (5) Allen, E., J . Opt. Soc. Am. 46, 430 (1956). (6) Am. SOC.Testing Materials, 1916
(136, 167) IS55 )
(573)
(46)
(569)
Arnold, R., Walker, 8. M., J . 8. African Cheni. Inst. 9, 80 (1956). Ayers, C:. W.,Anal. Chim. Acta 15, 77 (lC56). Ayms, G. H., Bolleter, W. T., A S A L CHEM. 29, 72 (1957). Ayres, G. H., TufAy, B. L., Forrester, J. S., Ibid., 27, 1742 (1955). Babkin, R. L., Elek. Xtantsii 27, No. 3, 19 (1956). Babko, A. K., Zhur. Neorg. Khina. 1, 48Ei (1956). Bacon, A., Milner, G. W. C., Anal. Chiin. Acta 15, 129 (1956). Ibid., p. 573. Bacon, A , , Milner, G. W. C., Atomic Energy Research Estab. (Gt. Britain) Rept. C/R 1637 (1955 I. Ibid., Cj'R 1749 (1955), Baghurst, H. C., Norman, V. J., ANAL.CHEY. 29, 778 (1957). Bandeliii, F. J., Pankrata, It. E., Zbid., 28, 218 (1956). Bandyopadhayay, D., J . Indian Chem. SOC.33,269 (1956). Banerjei:, D. K., ANAL.CHEX 29, 55 (1957). Banerjei:, G., Anal. Chim. Acta 16, 56 (1957). Ibid.,' p. 62; Naturwissenschaften 42, 177 (1955). Banks, (J. V., Bisque, R. E., ANAL. CHElcr 29, 522 (1957). Banks, C. V., Grimes, P. G., Bystroff, R. I., Anal. Chim. Acta 15, 367 (1956). C. V., Klingman, D. W., Banks, (33) Ibid., 15, 356 (1956). (34) Banks, C. V., LaMont, B. D., U. S. Atomic Energv Comm. 15C584 (1955). (35) Banks, C. V., Spooner, J. L., O'Laughlin, J. W.,ANAL. CHEY. 28, 1894 (1956). Barlot, ,J., M6m. poudres 36, 199 (1954). Barrera, P. A., Ortegui, S. J. Y. B., Ajinidad 32, 90 (1955). Beck, &I.T., Hantos, E., Acta Chim. Acad. Sci. Hung.8, 233 (1955). Beckman Instruments Inc., 2500 Fuller1,on Road, Fullerton, Calif., bulletin. BednBi., J., Ceskoslov. farm. 5, 26 (1956). Beers, R.. F., Jr., Biochem. J . 62, 492 (1!)56). BPlohUvek,, 0... Chem. listw- 50,. 1195 (1956). B6res, T., KirBly, I., Agrokemia ds Talajltcn 5, 245 (1956). Bergamiii, C., Maltagliati, M., Sperinwntale, sez. chim. biol. 6 , 65 (1956). Berman, S. S., Beamish, F. E., (45) McBrJ.de, W.A. E., Anal. Chim. Acta l,j,363 (1956). (46) Berman, S. S., McBryde, W.A. E., Analyct 81, 566 (1956). (47) Berntsson, S., ANAL. CHEM. 27, 1659 19551. (48) Ibid., 28, 1337 (1956). (49) Bertolacini, R. J., Barney, J. E. S., IIJbid., 29, 281 (1957). (50) Billman, J. H., Borders, D. B., Buehlw, J. A., Proc. Indiana Acad. Sci. 65. 68 (1955). (51) Bisby, H., Brown, L. H.,'Chapman, D. R., J . Sci. Instr. 33, 467 (1956). (52) Blackwell, A. T., Daniel, A. hf., Miller, J. D., ANAL. CHEM.28, 1209 ( 1956). (53) Blasius, E., Czekay, A,, 2. anal. Chem. 147,1(1955). ( 54) Blet, G., Congr. groupe. avancc. mhhod. anal. spectrog. produits m#. l l t h coongr. 1954, 91. I "
(83) (411) (676) (49) (391) (508) (14)
(85) (185)
(55, 46.9)
(3711 (81257y (3641 (357)
(550) (156) (5861 (34) (180) (200)
Race St., Philadelphia 3, Pa., "1956 Book of ASTM Methods for th;, Chemical Analysis of Matal.
(7) Anderson, B., Wright, W. B., U.S. Atomic Energy Comm., Y-900 (1952). (8) An'drewI-T. R., Gentry, C. H. R., Analyst 81, 339 (1956). (9) Andrus, S., Ibid., 80,514 (1955). (10) Andruze, R. A., ANAL.CHEM.29, 90 (1957). Anna;, E.; Can. J . Biochem. and Physiol. 33, 1010 (1955). Aoki, D., Iwayama, Y., Furusumi, I., Yakuzaigaku 16,9 (1956). Aoki, F., Repts. Gout. Ckem. Ind. Research Inst. Tokoyo, N o . 51, 419 (19561. (14) Adki, F:, Yuasa, T., Ibid., No. 51, 415 (1956).
VOL. 30, h10. 4, APRIL 1958
0
563
Bloch, L., Thienpont, R. A. J., Chem. V’eekblad 51,919 (1955). Bobtelsky, M., Blum, J., Anal. Chim. Acta 15, 62 (1956). Bobtelsky, M., Kertes, S., BuU. SOC. chim. France 1955, 328. Bobtelsky, M., Mayer, B., Anal. Chim.Acta 15, 164 (1956). Boltz, D. F., ed., “Colorinietric Determination of Nonmetals,” Interscience, New York, 1958. Bonnier, J. M., de’Gauemaris, G., Bull. SOC. chim. France 1955, 567. Bousez, A., Vanduel, C., Compt. rend. 27c congr. intern. chint. ind. Brussels, 1954, 2, Ind. chim. belge. 20, Spec. No. 348 (1955). Braicovich, L., Landi, M. F., Fonderie, No. 129, 381 (1956). Braude, E. A., Timmons, C. J., Photoelec. Spectrometry Group Bull., No. 6 , 139 (1953). Brice, B. A., Turner, h., J . Opt. Xoc. Am. 46, 293 (1956). Briggs, D. R., Garner, E. F., Montgomery, F., Smith, F., ANAL. CEEY. 28, 1333 (1956). Brown, E. G., Hayes, T. J., AnaZyst 80,755 (1955). Bruce, R. B., Howard, J. W., ANAL.CHEW28, 1973 (1956). Bruno, S., Accad. pugliese sci., attie. relaz 11, Pt. 2,409 (1953). Buchanan, E. B., Wagner, W., ANAL.CHEM.29, 754 (1957). Burchfield, H. P., Storrs, E. E., Contribs. Boyce Thompson Inst. 18, 310 (1956). Burriel, F., Taccheo, S. B., Anal. Chim. Acta 14, 553 (1956). Burton, J. D., Riley, J. P., Mikrochiin. Acta 1956, 1350. Bussmann, A., 2. anal. Clieni. 148, 413 (1956). Butt, L. T., Strafford, N., J . Appl. Chem. (London) 6 , 525 (1956). Buzzetti, A., Grisler, R., “Analisi Fotometria,” Ambrosiana, Milan, 1954. Cahn, L., ANAL. CHEW 28, 141 (1956). Caldin, E. F., Trorvse, F. W., Discusswm Faraday SOC.,No. 17,133 (1954). Calkins, R. C., Stenger, V. A., ANAL.CIIEM.28, 399 (1956). Cab, A., Mariani, A., Marelli, 0. M., Svensk. Farm. Tidskr. 60, 842 (1956). Catoggio, J. A., Anales direc. nac. quim. (Buenos Aires) 7,40 (1954). Cavell, A. J., J . Xci. Food Agr. 6,470 (1955). Cellini, R. F., Rodrigues, T. B., Anales real SOC. espaii. fZs. y qufm. ( M a d r i d ) 51B, 409 (1955). Cellini, R. F., Sanchez, L. G., Ibid., 52E, 111 (1956). Chen, P. S., Toribara, T. Y., Warner, H., ANAL. CHEY. 28, 1956 (1956). Cheng, K. L., Ibid., 28,1738 (1956). Cheng, K. L., Lott, P. F., Ibid., 28,462 (1956). Chierego, N., Arch. oceanog. e limol. 10, No. 3, 197 (1955). Ciuhandu, G., Acad. rep. popularc Romfne, Studii Cercetdri chim. 3,243 (1955). Claassen, A., Baamen, A., Anal. Chim. Acta 12, 547 (1955). Clark, L. J., Axley, J. H., ANAL. CHEM.27.2000 (1955). Clinch, J., ‘Anal. ’Chim. Acta 14, 162 (1956). Cline, R. E., Fink, R. M., ANAL. CHEY.28. 47 11956). Cogbill, E. ’C., ’Yoe,‘J. E.,Ibid., 29, 1251 (1957).
5&$
ANALYTICAL CHEMISTRY
Constituent Acetone p-Acetophenetiditle Acetyl Acetylamino sugaro Aliphatic aminea Aliphatic amines i’primary) Aliphatic amines (secondary) Aliphatic a-nitrohydroxy compounds Alkylbenzene siilfonates Alpha amino nitrogen Amino acids Aniline
Material
...
Pharmaceuticals Pectin, carbohydrate polymers
...
... Mixture of amines
... ...
Methylene blue
Blood Orange juice 2-Hydroxyethylaniline
Ninhydrin Ninhydrin Diazotization-Schiiffers acid Lauth reaction 2-Nitroaniline Thorium Nitration Chloramine T Permanganate Acetone-naphthol-ester Reineckate Nitration, reduction, and N-( 1-naphthy1)ethylenediamine Copper-biuret Paraformaldehyde
...
Food Biological Air Air
Benzonaphthol Betaine Biphenyl
Biological
Carbohydrates Chlorobenzene Chloropromazine Cycloserine
...
Resins Waste streams
...
Vegetables
...
Benzene Blood plasma
Cytochrome oxidase Detergents, anion: c Dialkyl phosphatc a Dialky1thiophospf.oric acids 4-Diamino-5-phen ylthiazole 3,5-Dinitro-o-cresd
Sewage
Diphenylamine Disulfiram Epichlorohydrin Esters Ethyl Cellosolve Ethylene glycol Ethylene oxide Fatty acids
Powders
Formaldehyde Formamide Fructose Fulvic acid Furfural Galactosamine Glucose Glucosamine Glutamic acid Glycolate ’
Hemin-cu Hemoglobin
Iron(II1)-acetohydroxamic acid Acetvlhexosamine Copier(II), chloroform Copper( 11)-salicylaldehvde Nitioprusside, acetaldehyde Chromotropic acid
Water, sewage
Aromatic aminea Ascorbic acid Aureomycin Benzene Benzidine
Biuret Bisphenyl-type epoxy rems 1-Butanol 7-Butyrolactone Carotene Carbonyl
Table IV. Photometric Detekrmination Method or Reagent Ref. Salicylaldehyde Diazotization, 2-naphthol
...
... Biological
Air
... ...
Waste streams Foods Cosmetics
Sucrose
... ... ... ...
... Carbohydrates
...
...
Protein hydrolyzates Carboxymethylcellulose Animal tissues Plasma
Sudan(II1) Iron(II1) Standard series 2,4:Dinitrophenylhydrazine Phenolsulfuric acid Nitration Iodic acid Sodium nitrotopentacyanoferroate Dimethyl-p-phenylenediamine Methyl green Trinitrobenzene Nickel(I1) Reinecke salt Methyl ethyl ketone extraction Sulfonation-oxidation Coppcr(I1) Acetylacetone Hydroxamic acid Sudan I11 Dichromate oxidation Chromotropic acid Copper(II), cobalt(II), chloroform Chromotropic acid Iron(II1) Guaiacol Indole Heteropoly blue Aniline p-Dimethylaminobenzaldehyde Phenolsulfuric acid 3,4-Dinitrobenzoic acid p-Dimethylaminobenzaldehyde Hydroxamic acid, iron(II1) Chromotropic acid Porphyrin-cu Differential
of Organic Compounds Constituent Material Hep tachlorocyclo... hexane Heptuloses Hexoses Sugar Tissue Hydrocortisone Plasma ... Hydroxamic acids Hydroxyproline 2-Hydroxy-4,5-dimethylpyrimidine 3-Indolacetic acid 17-Ketosteroids A4-3-Xetosteroids Keto acids 5-Ketogluconate
Collagen
..
...
Urine extracts Urine
... ...
Biological
..
8-Keto-~-gluconic acid Malic acid >Mannose hlenadione
Plants
Methanol
Ethanol Ethanol
Methoxyl
... ...
...
Morphine 1-Naphthol Nitromethane
Urine Napalm Nitroparaffine
Nitroparaffins Nucleic acids Oximes
Air
Biological
...
.. ...
Pentachlorophenol Pyrazinamide Parathion Phenol 3-(l-Phenylpropyl)-4hydroxy coumarin Pipecolic acid Pregnanediol Proline Pyridine Pentoses Phenols Polyethylene glycol mono-oleate Pyrocatechol Pyruvic acid Sarin
Cadaver
Biological Urine Biological Air Ethanol Sugar Phenolic resins
Urine Blood sugar
Thiophene
Benzene
Tetraethyl pyrophosphate Thuj aplicine Tocopherol Toluene Trichloroethylene Trypsin Tyrosine
Air
Vitamin &
Wood
Air Urine
p-Methylenebenzaldehyde 3,5-Dinitrobenzoic acid m-Dinitrobenzene Potassium tert-butoxide Hydroxylamine iron(II1) 1-Methyl-1-phenylhydrazine sulfate Molyb doar senic acid 2,7-Naphthalenediol Phenol-sulfuric acid 2,4;Dinitrophenylhydrazine Fuchsin-sulfurous acid Chromotropic acid Formaldehyde-c hromotropic acid Isonitrosomorphine Sodium cupribromide 1,2-Naphthoquinone-4sulfonate Griess
...
Iron(II1) formohydroxamate Methylene blue, oxidation, tetrabase Cobalt(I1) (2-Diethylarninoethyl)-l-
Methyl methacrylate Tablets
Sodium pentachlorw phenolate Streptomycin Sugar Sugars
Method or Reagent l-Chloro-2,4-dinitrobenzene Anthrone Phenol-sulfuric acid Carbazole-sulfuric acid Phenylhydrazine Iron( 111)formohydroxamate p-Dime thylaminobenzaldehyde Sulfanilic acid
... ... ... ... ... ... ...
...
... ...
... ..
naphthylamine oxalate p-Nitroaniline-pyridine Diazotized 4-nitroaniline Ninhydrin Talbot Ninhydrin Cyanogen bromide-aniline ... Phenol-sulfuric acid Nitrous acid Cobalt(I1) thiocyanate Iron(II1) Salicylaldehyde Benzidine Dianisidine
... Nitroprusside-ferricyanide Molybdoarsenate o-Aminobiphenyl Phenol-sulfuric acid p h i s i d i n e hydrochloride pDimethylaminobenzaldehyde Heteropoly blue Iron chelate Molybdophosphoric acid Nitration Pyridine, alkali Acid-base indicator Diazotized 2,4,6-tribromoaniline 2,4;Dinitrophenylhydrazine
Cohen, A. I Gordon, L., Zbid., 28. 1zL45 (l&6). Cohek, S.,.Kaliseyner, A,, Ibid., 29, llil (1957). Coppinr, W. C., Price, J. W., Meta!lurgia 53, 183 (1956). Coursier, J., Saulnier, J., And. Chim. Acta 14,62 (1956). Covingcon, L. C., Miles, M. J., ANAL.CHEM.28, 1728 (1956). Crawley, R. H. A., Anal. Chim. Acta 13,373 (1955). Critchf.eId, F. a:,Johnson, J . B., ANA],. CHEM.28, 436 (1956). Ibid., 29, 797 (1957). Cullis, C. F., Waddington, D. J., Anal. Chim. Acta 15, 158 (1956). Curry, D. R., Scholes, P. H., Metallurgia 54, 145 (1956). Curry, R. P., Mellon, M. G., ANA],.CHEM.28, 1567 (1956). Czensny, R., 2. Fisch. 1, 373 (1953); W a t e r Pollution Abstr. 27, 238 (1954). Dalziel, K., Discussions Faraday SOC.,No. 17, 128 (1954). Daniel J. W Gage, J. C., Analyst SI- -594 Dis-Sarma, - - ClbliSl B., Ray, J. N., Sci. and I
\----
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565
Feinstein, H. I., Anal. China. Acta 15, 141 (1956). Zbid., p. 288. Feldman, D. H., Cavagnol, J. C., ANAL.CHEM.28, 1746 (1956). Feldstein, hI., Klendshoj, N. C., J . Forensic Sci. 1,47 (1956). Fellegi, J., SlBina, L., Chem. zuesti 10, 314 (1956). Fenwick, M. L., Parker, V. A., Analyst 80, 774 (1955). Fernando, Q., Ludekens, W.L. W., Gnansooria, K., Anal. Chim. Acta 14, 297 (1956). Finkel’shteh, D. N., Zavodskaya Lab. 21, 1309 (1955). Ibid., 22, 648 (1956). Flaschka, H., Farah, N. Y., Z . anal. Chem. 152,401 (1956). Flaschka, H., Lassner, E., Mikrochinz. Acta 1956, 778. Flaschka, H., Sadek, F., 2. anal. Chem. 150,339 (1956). Fletcher, RI. H., Milkey, R. G., ANAL,CHEX 28, 1402 (1956). Focht, R. L., Schmidt, F. H., Dowling, B. B., J . Agr. Food Chem. 4,546 (1956). Fournier, R. RI., Chim. & Ind. (Paris) 76,246 (1956). Frank, A. J., Goulston, A. B., Decutis, A. A., ANAL.CHERI. 29, 750 (1957). Frear, D. S., Burrell, R. C., Zbid., 27,1664 (1955). Freeland, M. Q., Fritz, J. S., Ibid., 27, 1737 (1955). Freund, H., Hammill, IC. H., Bissonnette, F. C., U. S. Bur. Mines, Rept. Invest. 5242 (1956). Fulton, J. W.,Hnstings, J., ANAL. CHEM.28, 174 (1956). Gagliardi, E., Haas, W.,Z. anal. Chem. 147, 321 (1955). Gann, W., Ibid., 150,254 (1956). Garcia, F. C., Ruiz, R. G., Alvarez, F. M., Anales edafol. y fisiol. vegetal ( M a d r i d ) 15,57 (1956). Gassner. IC.. Z . anal. Chem. 153.
No. 12,52. Gladyshev, V. P., Tolstikov, G. A,, Zauodskaya Lab. 22, 1166 (1956). Glegg, R.E., ANAL.CHEM. 28, 532
.---
(1956).
I-
Glen,, D. N., Robertson, R. E., J . Sci. Instr. 33, 27 (1956). Goddau, R. F., LeBlanc N. F., Wright, C. Rf., ANAL. HEM. 27, 1251 (1955). Golay, M. S. E., J . Opt. SOC.Am. 45,430 (1955). Goldenberg, H., ANAL. CHEW 28, 1003 (1956). Golterman, H. L., Koninkl. Ned. Akad. Wetenschap., Proc. Ser. B, 58, 109 (1955). ANALYTICAL CHEMISTRY
(176) Goodhan, A. E., St,ark, J. B., ANAL.CHIZM. 29, 283 (1957). (177) Gorbach,. G... Mikrochim. Acta 1955, 879. Gordon, L., Feibush, A. AI., ANAL. CHEX 27, 1050 (1955). Gorsuch, T. T., Posner, A. hf., Nature 17t, 268 (1955). Goto, H., ICakita, Y., J a p a n Analyst 3,299 (1954). Goto, H., I
