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Volume 5, Issue 10
Displaying 1-12 of 12 articles from this issue
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Daizo SHIMOE1956 Volume 5 Issue 10 Pages 547-554
Published: 1956
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSAn abnormal reaction of aliphatic primary amines in the Van Slyke ethod is well known, and its mechanism has been clarified in some respects; but little is known with respect to the aromatic series. By the u e of the preceeding method (I), quantitative determinations of p-nitroaniline, aniline hydrochloride, and sulfanilic acid have been carried out with results of considerable (+) effect in all cases. This error was found to be due to the hydroxyl group produced by the decomposition of the diazonium salt. Moreover, it is affected by three factors : (1) the concentration of sobium nitrite in the solution, (2) the time of standing of the diazonium salt before heating, and (3) the time of heating of the solution. The cause may be attributed to the acceleration of nitrosoation and formation of oxime by (1) snd (2), snd the increased rate of decomposition of oxime by (3). The method of using nitrous acid in slight excess, for the above reason, was investigated, and was found that the determination of aniline hydrochloride can be made with fair accuracy. Thus a method of suppressing the abnormal reaction of aromatic amines is made possible.
Based on the knowledge obtained in the preceeding experiment (II), quantitative determinations of 16 kinds of aromatic primary amines have been carried out with the use of sodium nitrite in a very slight excess. The sample (520 mg) in 2 ml hydrochloric or acetic acid or a dilute alkali, 1 ml 4 M CuCl2 as a decomposition catalyst, and 2 ml 3 M KBr as an accelerator for the reaction are placed in the apparatus. The air in the apparatus is replaced by CO2 gas, and 0.5 ml 1 % NaNO2 is added, the mixture allowed to stand for 2 min. at room temperature, and then heated for 45min at 145°C. The nitrogen gas evolved is collected in an azotometer by introducing CO2 gas at a rate of 56 ml/min. The time required for the determination was 35 min. Using HNO2 in an amount 1.41.6 times the theoretical amount gave the best result and it is desirable to be at least within the range of 1.22.0 times, while the change of other factors even to a considerable extent gave less effect. Results with relative error 0.51.0 % were obtained. Samples reacting slowly with HNO2 can be analyzed by this method. Also, primary amines having hydroxyl groups can be determined with good accuracy.View full abstractDownload PDF (1696K) -
Yukio IEKI1956 Volume 5 Issue 10 Pages 554-556
Published: 1956
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSConway's microdiffusion analysis has been applied to the determination of the residual ammonia in phenol-formaldehyde molded materials. This method was found to be more accurate than the method of A. S. T. M. D-834-49. It requires only a 0. 5 g sample while the latter uses 10 g sample. The reagents used for Conway's microdiffusion analysis are as follows : (a) a mixed indicator composed of an alcoholic solution containing 0. 033 % bromcresol green and 0. 066 % methyl red; (b) boric acid reagent composed of 10 g. of pure boric acid introduced into a liter measuring flask to which are added 200 ml alcohol and about 700 ml distilled water, and then 10 ml of the mixed indicator (the solution showing a faint red color with the addition of a little alkali or hydrochloric acid, and being made up to the mark with water) ; (c) standard N/50 HCl solution; and (d) 40 % NaOH solution. Preparation of sample: samples are filed and ground to pass through a 150-mesh sieve, and these are kept in tightly stoppered flasks before analyses. Procedure: one ml of the boric acid reagent withindicator is placed in an inner chamber, and 0. 5 g. sample is carefully put into an outer chamber. The lid with ground glass joint is fixed in position with grease and 2 ml 40 % sodium hydroxide solution is introduced into the outer chamber, allowed to stand for 24 hours. The green colored solution in the inner chamber is titrated with N/50 HCl through a horizontal microburette until it gives red coloration. Calculation: percent of NH3 = SD/C×100, where S=ml of N/50 HCl used; D=weight of NH3 equivalent to 1 ml N/50 HCl; C=weight of sample.View full abstractDownload PDF (516K) -
Chemical Analysis of Antimony by Means of OxineIchiro KUDO1956 Volume 5 Issue 10 Pages 556-559
Published: 1956
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSComplex salts of Sb (III) and Sb (V) formed by reaction with oxine have been investigated and the following information obtained : ( 1 ) a complex salt of Sb (III), prepared by treating a solution of antimony chloride successively with tartaric acid and with oxine to precipitate what had heretofore been believed to have the formula SbO C9H7NO (C9H6NO)2, was confirmed to be Sb (C9H6NO)3, the same as that prepared without the addition of tartaric acid; ( 2 ) complex salts of Sb( V ) with oxine, dichlorooxine, and dibromooxine were prepared, and it was found that these compounds are useful for the separation of Sb (V) from the other ions and for its quantitative determination.View full abstractDownload PDF (658K) -
Zenzo TAMURA, Kazuko KAWAHARA1956 Volume 5 Issue 10 Pages 559-561
Published: 1956
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSMeissner's flame color test for tin has been investigated. The test is carried out as follows: The sample is mixed with concentrated hydrochloric acid and zinc, a test tube filled with water is dipped in this solution and the tube is held over the flame of a Bunsen burner to give a characteristic blue flame.
The addition of zinc is found unnecessary in this case but the presence of hydrochloric acid is essential for this flame color reaction. The Sn4+ (0.010.05%) is distilled with hydrochloric acid vapor by heating the hydrochloric acid solution at about 150°C and the vapor gives a characteristic blue color in the Bunsen flame. Although Sn2+ is not distilled with hydrochloric acid, it gives colored flame by heating the hydrochloric acid solution in the Bunsen flame as it is rapidly oxidized to Sn4+.
The above results confirmed that the flame color reaction for tin depends chiefly upon the volatility of SnCl4 (bp 114°C) and the reduction to SnH4 as reported by Meissner is unnecessary.View full abstractDownload PDF (474K) -
Shinzo OKADA, Nobuatsu WATANABE, Yuichi OMOTE1956 Volume 5 Issue 10 Pages 562-566
Published: 1956
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe analysis of metallic sodium heretofore has been made by the titrimetric method, employing its solution oxidized by alcohol. In using this method unsatisfactory results have been obtained, which are due to the presence of NaOH as an impurity. Therefore a more accurate method to determine the amount of hydrogen produced by the oxidation of sodium with alcohol has been carried out. In this method, the presence of NaOH or Na2CO3 in the metal does not cause any error. Since the gas analysis requires careful caution for the measurents of the gas volume which is sensitve for the change of temperature and pressure, the necessary apparatus and reagent have been investigated. The method can be operated simply in a short time with better accuracy than the titrimetric method. A table for correction of the volume of gas is presented in order to make a rapid calculation. The standerd deviation of measurements was 0. 009 % and it showed higher accuracy than the titrimetric method.View full abstractDownload PDF (804K) -
Zenzo TAMURA, Motoichi MIYAZAKI1956 Volume 5 Issue 10 Pages 566-570
Published: 1956
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIn connection with the preceding rep rt dealing with the complete analysis of 24 metal ions, the complete analysis of 20 anions has been investigated in this experiment, The sample solution was prepared so as to contain 0. 20. 5 % of each anion as its Na salt and the solution was adjusted to contain 5% Na2CO3. A 0. 0050. 01-ml portion of the solution was spotted on a strip of Toyo filter paper No. 3 and it was tested by descending paper chromatography to separate and identify all the anions by the use of 3 kinds of developers giving specific and selective color reactions for detection. Three kinds of developers were acetone:water (10:1) for Br-, Cl-, I-, CNS-, ClO3-, BrO3- and NO3-; butanol: methanol: water: (1:3:1) for F-, NO2-, S2O32-, SO42-, CrO42-, IO3-, AsO33-, Fe (CN)64-, Fe(CN)63-, and BO2-, and butanol saturated with 2 N HNO3 for C2O42-, AsO43-, and PO43-.View full abstractDownload PDF (840K) -
Separation of Rare EarthsMasafumi MAKI1956 Volume 5 Issue 10 Pages 571-573
Published: 1956
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSBy utilization of the formation of a complex salt of citric acid, separation of Y3+, La3+, Ce3+, Pr3+, and Nd3+ by electrochromatography has been carried out and the following results obtained: 1) citric acid-NaCl solution as an electrolyte gave good results by adjusting the concentration of citric acid to 0.01250.05 M when the concentration of NaCl was 0.05 M, or the concentration of NaCl to about 0.05 M when the concentration of citric acid was 0.05 M; 2) the effects on the separation of the rare earths produced by changing the pH of 0.05 M citric acid-0.05 M NaCl solution through the addition of NH4OH or HCl were found to be such that lower pH values caused the migration of rare earths toward the cathode, while increased pH values resulted in decrea sed mobility, and at pH 2.83.0, the direction of migration was reversed. Further increase in pH value caused an increase in the velocity of migration toward the anode, and finally it had a tendency to show a definite value. Mutual separation of rare earths at lower pH values was inefficient, but it improved with an increase in pH value, and it was the best at pH 2.6. The direction of migration was then reversed and the separation returned to an optimum at pH 3.05, further increase in pH value being ineffective. As an example, the separation of 5 kinds of rare earths was possible from their differences in migration velocity at pH 2.6 and pH 3. 05, with the exception of Pr and Nd :
pH 2.6 Y -0.27, La - 0.53, Ce - 0.43, Pr - 0.33.
pH 3.05 Y 0.41, La 0.19, Ce 0.30, Pr 0.35, Nd 0.37
(Unit : μ/sec/v/cm) (-sign indicates mobility toward the cathode).View full abstractDownload PDF (401K) -
[in Japanese]1956 Volume 5 Issue 10 Pages 574-575
Published: 1956
Released on J-STAGE: June 30, 2009
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[in Japanese]1956 Volume 5 Issue 10 Pages 575-576
Published: 1956
Released on J-STAGE: June 30, 2009
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[in Japanese]1956 Volume 5 Issue 10 Pages 576-577
Published: 1956
Released on J-STAGE: June 30, 2009
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1956 Volume 5 Issue 10 Pages 578-595
Published: 1956
Released on J-STAGE: June 30, 2009
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[in Japanese]1956 Volume 5 Issue 10 Pages 596-601
Published: 1956
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESS
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