scholarly journals Spectrophotometric Measurement Of The Stoichiometry Of Formaldehyde And Plasma Albumin Reaction In Water Solution Using The Method Of Continous Variation (Job’s Method ) And The Mole Ratio Method

2013 ◽  
Vol 5 (6) ◽  
pp. 42-45
Author(s):  
Keyword(s):  
Water Solution ◽  
Ratio Method ◽  
Spectrophotometric Measurement ◽  
Plasma Albumin ◽  
Mole Ratio Method ◽  
Job's Method ◽  
Reaction In Water

scholarly journals Preconcentration and Spectrophotometric Determination of Copper and Nickel in some Medicinal PlantsafterCloud Point Extraction

2018 ◽  
Vol 9 (SPL1) ◽  
Author(s):  
Azhar A Ghali ◽  
Ashwoq S Hussein
Keyword(s):  
Cloud Point ◽  
Limit Of Detection ◽  
Variation Method ◽  
Ratio Method ◽  
Relative Standard ◽  
Aqueous Layer ◽  
Mole Ratio Method ◽  
Triton X ◽  
Job's Method

In this work,Cloud point extraction (CPE) methodology as an one green chemistry method is used for extraction, enrichment and determination ofNi (II) and Cu (II) in the somemedicinal plants,by use organic reagent2-[ (6-Methyl-2-Benzothiazolyl)azo]-4-Chloro Phenol (6-MeBTAClP) for formationthe extracted complexes into micelles of Triton X-114 as a mediated extractant at65,70 C0 respectively. The extracted product in densityhigh (cloud point layer )is separated from the aqueous layer by centrifugation for 15 min and dissolved in 0.5 mLfrom ethanol followed the determination of Ni (II) and Cu (II)by using spectrophotometry at a wavelength maximum of 644 and 598 nm respectively. The optimum conditions established as pH, The linear range of Ni (II) and Cu (II)along with limit of detection,precision expressed as relative standard deviation for seven replication measurements and the recovery range were obtained for Ni (II) and Cu (II) ions,respectively. The complex s identified by UV-Visible and IR spectra. The mole ratio method and continuous variation method (Job’s method)also investigated.

Extractive Spectrophotometric Method for the Determination of Glibenclamide by Ion-Pair Complex in Pure Form and Pharmaceutical Formulation

2019 ◽  
Vol 9 (o3) ◽  
Author(s):  
RUAA MUAYAD MAHMOOD ◽  
HAMSA MUNAM YASSEN ◽  
SAMAR , NAJWA ISSAC ABDULLA AHMED DARWEESH ◽  
NAJWA ISSAC ABDULLA
Keyword(s):  
Spectrophotometric Method ◽  
Molar Absorptivity ◽  
Ion Pair ◽  
Pharmaceutical Formulation ◽  
Ratio Method ◽  
Colored Complex ◽  
Colored Product ◽  
Method Of Continuous Variation ◽  
Job's Method

Simple, rapid and sensitive extractive spectrophotometric method is presented for the determination of glibenclamide (Glb) based on the formation of ion-pair complex between the Glb and anionic dye, methyl orange (MO) at pH 4. The yellow colored complex formed was quantitatively extracted into dichloromethane and measured at 426 nm. The colored product obeyed Beer’s law in the concentration range of (0.5-40) μg.ml-1. The value of molar absorptivity obtained from Beer’s data was found to be 31122 L.mol-1.cm-1, Sandell’s sensitivity value was calculated to be 0.0159 μg.cm-2, while the limits of detection (LOD) and quantification (LOQ) were found to be 0.1086 and 0.3292 μg.ml-1, respectively. The stoichiometry of the complex created between the Glb and MO was 1:1 as determined via Job’s method of continuous variation and mole ratio method. The method was successfully applied for the analysis of pharmaceutical formulation.

Magnetophoretic mole-ratio method in solvent extraction systems

2020 ◽  
Vol 1111 ◽  
pp. 60-66
Author(s):  
Hitoshi Watarai ◽  
Mariko Kurahashi
Keyword(s):  
Solvent Extraction ◽  
Ratio Method ◽  
Mole Ratio Method

scholarly journals 2-Hydroxy-5-methylbenzophenone oxime(HMBO) as an Analytical Reagent for Gravimetric Determination of Cu(II)

2007 ◽  
Vol 4 (1) ◽  
pp. 97-102 ◽  
Author(s):  
S. K. Shingadia ◽  
K. K. Desai
Keyword(s):  
Copper Ion ◽  
Molar Absorptivity ◽  
Ratio Method ◽  
Formation Reaction ◽  
Gravimetric Determination ◽  
Analytical Reagent ◽  
Gibb’S Free Energy ◽  
The Stability ◽  
Job's Method

2-Hydroxy-5-methylbenzophenone oxime (HMBO) was developed as a new analytical reagent for the gravimetric determination of divalent copper ion. In pH rang of 3.0 to 6.0, the reagent gives a buff colored precipitate with Cu(II). Job’s method and mole ratio method revealed that the stoichiometry of the complex is 1:2 (metal: ligand). Beer’s law is obeyed up to 61.25 ppm of Cu(II). Molar absorptivity and Sandell’s sensitivity at 400 nm were found to be 6.32 × 102L mol-1cm-1and 0.359 μg/cm2respectively. The stability constant of Cu(II)-HMBO complex is found to be 2.43 × 109. Gibb’s free energy change for complex formation reaction was found to be -12.88 Kcal/mol. The reagent can be used for the analysis of brass and alloy.

scholarly journals Determination of Stability Constants and Thermodynamic parameters of Cefotaxime –Fe(III) Complex at Different Temperatures

2020 ◽  
Vol 45 (4) ◽  
Author(s):  
O. V. Ikpeazu ◽  
I. E. Otuokere ◽  
K. K. Igwe
Keyword(s):  
Stability Constants ◽  
Chelating Agent ◽  
Continuous Variation ◽  
Molar Ratio ◽  
Variation Method ◽  
Ratio Method ◽  
Lactam Antibiotic ◽  
Different Temperatures ◽  
Mole Ratio Method ◽  
Continuous Variation Method

Cefotaxime, a β-lactam antibiotic, has a structure which enables it to act as a chelating agent. The formation of Fe(III) complex with cefotaxime has been studied colorimetrically at an absorption maximum of 480 nm at different temperatures. The data showed that Fe(III) and cefotaxime combine in the molar ratio of 1:1  at pH 7.4 with ionic strength maintained using 0.1M KNO3. The stability constants of the complex were calculated to be 1.56 - 1.90 x 104 by continuous variation method and 1.34 - 1.71 x 104 by mole ratio method at 25 and 40 oC respectively. ∆HƟ values for the complex were calculated to be -1.02 x 104 and -1.05 x 104 J by continuous variation method and mole ratio method respectively. ∆GƟ of the complex were calculated to be -2.44 – (-2.51) x 104 J by continuous variation method and -2.41- (- 2.48)  x 104 J by mole ratio method at 25 and 40 oC.  ∆SƟ of the complex were calculated to be 2.44 - 2.51 x 104 J/K by continuous variation method and -2.41 -2.48) x 104 J/K by mole ratio method at 25 and 40 oC respectively. Cefotaxime is a good chelating agent and can be an efficient antidote in the therapy of copper overload or poisoning.  

Die Isopolymolybdationen in wäßrigen Medien im Bereich Z ≦ 1,14 / Concerning Isopolymolybdate Ions in Aqueous Media in the Range Z ≦ 1.14

1980 ◽  
Vol 35 (1) ◽  
pp. 45-56 ◽  
Author(s):  
Karl-Heinz Tytko ◽  
Georgios Petridis ◽  
Bernd Schönfeld
Keyword(s):  
Main Product ◽  
Structural Parameters ◽  
Aqueous Media ◽  
Ratio Method ◽  
Intensity Difference ◽  
Ionic Medium ◽  
Theoretical Investigations ◽  
Detailed Evaluation ◽  
Mole Ratio Method ◽  
Statistical Certainty

The system H+/MoO42- was investigated by Raman spectroscopy in the range Z = 0 to 1.14 at initial concentrations CMoO₄ 2- = 0.02 to 2M and concentrations of the ionic medium CMe+ = 2CMoO₄ 2- to 3M Me(Cl,NO3) (Me=Li, Na, K,NH4 , Mg/2). The mole-ratio method and intensity difference diagrams do not indicate any species between MoO42- and Mo7O246- contrary to propositions in recent papers. A detailed evaluation of the extensive data shows the possible portion of such species to be < 3 % , this value having a statistical certainty of 95%. Comparing the solutions having Z = 1.1 by fingerprint procedures, in all cases Mo7O246- is the first main product (detectable by static methods) irrespective of the nature and concentration of the ionic medium. Thus, Mg2+ ions do not influence the course of aggregation of molybdate ions as has been proposed in the literature. This is in accordance with theoretical investigations since the Mo7O246- ion has the distinction of a number of favourable structural parameters in the system that become operative in case of scarcity of H+ ions.

scholarly journals 2-Hydroxy-4-n-propoxy-5-bromoacetophenone oxime as an Analytical Reagent for Gravimetric Determination of V(V)

2009 ◽  
Vol 6 (2) ◽  
pp. 303-307 ◽  
Author(s):  
Ambily P. Nair ◽  
J. Christine
Keyword(s):  
Molar Absorptivity ◽  
Ratio Method ◽  
Gravimetric Determination ◽  
Pentavalent Vanadium ◽  
Analytical Reagent ◽  
Gibb’S Free Energy ◽  
The Stability ◽  
Ph Range ◽  
Job's Method

2-Hydroxy-4-n-propoxy-5-bromoacetophenone oxime (HnPBAO) was developed as a new analytical reagent for the gravimetric determination of pentavalent vanadium ion. In the pH range 4.0-6.0, the reagent gave a brown coloured precipitate with V(V). Job’s method and Mole ratio method revealed that the stoichiometry of the complex is 1:1 (metal: ligand). Beer’s law is obeyed up to 20.38 ppm of V(V). Molar absorptivity and Sandells sensitivity at 450 nm were found to be 10.22 × 102L/mol/cm and 0.049 µg/cm2respectively. The stability constant of V(V)-HnPBAO complex is found to be 1.195 × 106. Gibb’s free energy change for complex formation reaction was found to be –8.34 kcal/mol. The reagent can be used for the analysis of vanadium in ferro-vanadium alloys.

Study of iron(II) complexes with halides and thiocyanate in acetonitrile

1970 ◽  
Vol 48 (9) ◽  
pp. 1414-1419 ◽  
Author(s):  
Byron Kratochvil ◽  
Robert Long
Keyword(s):  
Formation Constants ◽  
Ratio Method ◽  
Mole Ratio Method ◽  
Stepwise Formation

In acetonitrile, iron(II) forms stable 1:1 complexes with chloride, bromide, and iodide and both 1:1 and 1:2 complexes with thiocyanate. Stepwise formation constants for the complexes were determined spectrophotometrically by a mole-ratio method. The log K values are: FeCl+, 5.8; FeBr+, 5.5; FeI+,4.3; Fe(SCN)+, 5.5; and Fe(SCN)2, 3.7.

scholarly journals DEVELOPMENT OF EXTRACTIVE SPECTROPHOTOMETRIC METHOD FOR THE DETERMINATION OF IRON (III) WITH SCHIFF BASE 2-[(2-HYDROXYPHENYLIMINO) METHYL]-4-NITROPHENOL

2016 ◽  
Vol 8 (4) ◽  
pp. 89 ◽  
Author(s):  
Datta B. Mandhare ◽  
Vasant D. Barhate
Keyword(s):  
Aqueous Solution ◽  
Schiff Base ◽  
Spectrophotometric Method ◽  
Molar Absorptivity ◽  
Maximum Absorption ◽  
Ratio Method ◽  
Pharmaceutical Samples ◽  
Mole Ratio Method ◽  
Ph Range

Objective: A simple spectrophotometric method has been developed for the determination of Iron (III) by using Schiff base 2-[(2-hydroxyphenylimino) methyl]-4-nitrophenol [HPIMNP].Methods: HPIMNP extracts Fe (III) quantitatively (99.95%) into chloroform from an aqueous solution of pH range 4.0-6.0.Results: The chloroform extracts show maximum absorption at 510 nm (λ max). Beer’s Law is obeyed over the Fe (III) concentration range of 0.5 to 20.0 µg/ml. The Molar absorptivity and Sandell’s sensitivity for Fe–HPIMNP system is 5000 L mol ˉ1 cmˉ1 and 0.011 µg cmˉ2respectively. The composition of extracted species is found to be 1: 3 [Fe-HPIMNP] by Job’s continuous variation and Mole-ratio method. Interference by various ions has been studied.Conclusion: The proposed method is rapid, sensitive, reproducible and accurate and it has been satisfactory applied for the determination of Iron in Pharmaceutical Samples.

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