Spectrophotometric Determination of Iron(Ⅲ) after Separation by Adsorption of its pyrrolidinedithiocarbamate on Naphthalene

A method is presented for the spectrophotometric determination of trace amounts of iron(Ⅲ) after adsorption of its pyrrolidinedithiocarbamate with microcrystalline naphthalene. Iron(Ⅲ) forms a stable chelate with pyrrolidinedithiocarbamate ammonium salt and this chelate is quantitatively adsorbed onto microcrystalline naphthalene at room temperature in the pH range of 2.9-6.6. The mixture of the chelate and naphthalene is dissolved in chloroform. The chelate in naphthalene-chloroform solution obeys Beer's law over the range 2.3-49 μg of iron(Ⅲ) in 10 ml of chloroform. The molar absorptivity is 1.1 x 104 l.mol-l・cm-l at 357 nm, the sensitivity being 4.9 x 10-3 μg/cm2 for the absorbance of 0.001. The relative standard deviation for the present analysis of iron(Ⅲ) is 1.0% for ten determinations. In the present experiments, the effect of variables such as pH, amounts of reagent and naphthalene, digestion and shaking time and diverse ions have been examined. The method has been applied to the determination of iron(Ⅲ) in reference and environmental samples and results compared with l,lO-phenanthroline method

Spectrophotometric Determination of Cadmium after Separation by Adsorption of Its Oxinate on

A procedure is presented for the spectrophotometric determination of cadmium after separation by adsorption of cadmium oxinate on microcrystallin naphthalene. A water-insoluble oxinate formed with cadmium is quantitatively adsorbed from aqueous solution with microcrystalline naphthalene. This oxinate has an absorption maximum at 395 nm. The optimum pH range for the adsorption is 5.8-9.2. The molar absorptivity is 4.5 x 103 l·mol-l.cm-l at 395 nm, the sensitivity being 2.5 x 10-2 μg of cadmium per cm-2 for an absorbance of 0.001. 87 Ten samples containing 100 μg of cadmium gave a mean absorbance of 0.403 with a relative standard deviation of 2.8%. Effect of optimum wavelength, amounts of reagent and naphthalene, digestion time, standing time, shaking time and diverse ions are studied

Spectrophotometric determination of bismuth(Ⅱ) after separation by coprecipitation of its 2-mercaptobenzothiazole complex with naphthalene

A method is described for the spectrophotometric determination of trace amounts of bismuth(Ⅱ) after separation by coprecipitation of its 2-mercaptobenzothiazole complex with naphthalene. 2-mercaptobenzothiazole reacts with bismuth(Ⅱ) to form a water-insoluble complex, which is easily coprecipitated with micro-crystalline naphthalene and the resulting mixture of the complex and naphthalene is dissolved in DMF. The absorbance of the solution is measured at 394 nm to determine the trace amounts of bismuth(Ⅱ). The various factors such as pH, amounts of reagent and naphthalene, shaking time, standing time and diverse ions are studied

Solid-Liquid Separation after Liquid-Liquid Extraction. -Spectrophotometric Determination of Bismuth after Extraction of Its 2-mercaptobenzothiazole Complex with Molten Naphthalene-

A new reagent, 2-mercaptobenzothiazole,sodium salt is described for the spectrophotometric determination of bismuth(II) after extraction of bismuth complex with molten naphthalene. This reagent reacts with bismuth(II) to form a water-insoluble complex. The complex is insoluble in chloroform or benzene, but easily soluble in molten naphthalene. The extracted mixture of bismuth complex and naphthalene is dissolved in dimethylformamide and the trace amounts of bismuth are determined spectrophotometrically. The linearity between the absorbance and bismuth concentration is held for 10 - 200μg of bismuth in 10 ml of dimethylformamide. The molar absorptivity was calculated to be 1.1 x 10 4 l.mol-l･cm-l , the sensitivity 0.020 μg of bismuth per cm2 for the absorbance of 0.001 and the relative standard deviation 0.76 % for ten times determinations

Spectrophotometric Determination of Iron (III) after Separation by Adsorption of its N-Benzoyl-N-Phenyl Hydroxylamine Complex on Naphthalene

The novel method for the spectrophotometric determination of trace amount of iron (III) after separation of its BPA complex by adsorption on microcrystalline naphthalene is described. The epsilon/ sub max/ of the DMF solution of the adsorbate containing iron (III)- BPA complex at lambda/sub max/ 437 nm has been found to be 4.47 X 10/sup 3/. The effect of variables and interfering ions on the efficacy method has been studied. Sensitivity (in Sandell's notation) is 1.25 X 10/sup -2/ micro g of iron (III)/cm/sup 2/ and at a mean absorbance of 0.40000 is 1.25%. The method is useful for the analysis of standard reference materials and environmental samples. The results are comparable with those obtained using ortho phenanthroline

Spectrophotometric Determination of Iron(III) after Separation by Adsorption of its Pyrrolidinedithiocarbamate on Nephthalene

A method for the spectrophotometric determination of trace amounts of iron(III) after adsorption of its pyrrolidindeithiocarbamate on naphthalene is presented. Iron(III) forms a water-insoluble chelate with ammonium pyrrolidinedithiocarbamate in the pH range 2.9-6.6. This chelate is quantitatively adsorbed onto mycrocrystalline naphthalene at room temperature. The effects of variablesm, such as pH, amount of reagent and napthalene, digestion and shaking time, and diverse ions, have been examined. The method has been applied to the determination of iron(III) in standard reference and environmental samples and the results compared with 1,10-phenanthroline method

Spectrophotometric Determination of Magnesium after Separation by Adsorption of its Oxinate on Microcrystalline Naphthalene

A procedure is presented for the spectrophotometric determination of magnesium af,ter separation by adsorption of magnesium oxinate on microcrystalline naphthalene. A water-insoluble oxine chelate produced with magnesium is quantitatively adsorbed from aqueous solution with microcrystalline naphthalene. This chelate has an absorption maximum at 382 nm. The optimum pH range for the adsorption is 8.6- 10.8. The molar absorptivity is 4.1 x 103 l mol-l·cm-l . the sensitivity being 5.9 K 10-3 pg per ㎠ for the absorbance of 0.001. Ten determinations of the sample solution containing 30 pg of magnesium, prepared by the general procedure, gave a mean absorbance of 0.506 with a relative standard deviation of 2.5%. 200 min

Spectrophotometric determination of copper after separation by adsorption of its APDC complex on naphthalene

The copper APDC complex was adsorpted on microcrystalline naphthalene to determine the trace amounts of copper. The complex has an absorption maximum at 435 nm. The optimum pH range for the adsorption is 1.5-10.5. Beer's law was obeyed over the range of 2.5-48 μg of copper in 10 ml of dimethylformamide. The molar absorptivity was 1.3 xlO 4 l·mol -1·c-m1 ,the sensitivity of the complex as expressed by the Sandell's notation being 4.8xlO-3 μg of copper per ㎠. Sample solution ontaining 25 μg of copper was analyzed 10 times by the recommended procedure. The mean absorbance was 0.500 with relative standard deviation of 0.89%. The other factors such as amounts of reagent and naphthalene, standing time, shaking time and diverse ions were studied