The determination of the stoichiometry and stability constant of weak complexes in solution: a restatement of the "straight-line" method

1983 ◽  
Vol 61 (6) ◽  
pp. 1100-1102 ◽  
Author(s):  
Aurelio Beltrán-Porter ◽  
José A. Ramírez
Keyword(s):  
Stability Constant ◽  
Stoichiometric Ratio ◽  
Complex Species ◽  
Line Method ◽  
Straight Line ◽  
Weak Complexes ◽  
The Stability ◽  
Degree Of Condensation ◽  
Straight Line Method

Usually, to establish the degree of condensation of a complex species in solution, primarily when it is a weak complex, is more cumbersome than to determine the stoichiometric ratio itself. The present work describes a modification of the Asmus method in order to render it suitable for the determination of the actual stoichiometric coefficients and the stability constant of weak complexes whatever the degree of condensation may be.

Synthesis and solvatochromic studies of 2- amino-3-phenolazo1-(4-sulfophenyl)-3-methyi-5-pyrozolone and use it for the determination of trace amount of Nickel (II) in blood samples

2016 ◽  
Vol 5 (10) ◽  
pp. 4920
Author(s):  
Amar M. Ali ◽  
Hussain. J. Mohammed*
Keyword(s):  
Stability Constant ◽  
Trace Amount ◽  
Benzenesulfonic Acid ◽  
Determination Method ◽  
Blood Samples ◽  
Determination Of Nickel ◽  
Normal Human ◽  
The Stability ◽  
Normal Human Blood

A new, simple, sensitive and rapid spectrophotometric method is proposed for the determination of trace amount of Nickel (II). The method is based on the formation of a 1:2 complex with 4-(4-((2-hydroxy-6-nitrophenyl) diazenyl) -3-methyl-5-oxo-2, 5-dihydro-1H-pyrazol-1-yl) benzenesulfonic acid (2-ANASP) as a new reagent is developed. The complex has a maximum absorption at 516 nm and εmax of 1. 84 X 105 L. mol-1. cm-1. A linear correlation (0. 25 – 4. 0μg. ml-1) was found between absorbance at λmax and concentration. The accuracy and reproducibility of the determination method for various known amounts of Nickel (II) were tested. The results obtained are both precise (RSD was 1. 2 %) and accurate (relative error was 0. 787 %). The effect of diverse ions on the determination of Nickel (II) to investigate the selectivity of the method were also studied. The stability constant of the product was 0. 399 X 106 L. mol-1. The proposed method was successfully applied to the analysis of diabetes blood and normal human blood. 

Determination of the Stability Constant of the Calcium Dioxalate Complex

Urolithiasis ◽  
1981 ◽  
pp. 447-451
Author(s):  
John R. Burns ◽  
Birdwell Finlayson ◽  
Arthur Smith
Keyword(s):  
Stability Constant ◽  
The Stability

scholarly journals New Spectrophotometric Method for Determination of Cadmium

2009 ◽  
Vol 6 (s1) ◽  
pp. S496-S500
Author(s):  
K. S. Parikh ◽  
R. M. Patel ◽  
K. N. Patel
Keyword(s):  
Stability Constant ◽  
Spectrophotometric Method ◽  
Basic Medium ◽  
Buffer Solution ◽  
Solution Ph ◽  
Yellow Colour ◽  
Maximum Absorbance ◽  
The Stability

The reagent 2-hydroxy-4-n-butoxy-5-bromopropiophenone thiosemicarbazone (HBBrPT) has been used for the determination of Cd(II) by using spectrophotometric method. The reagent HBBrPT gave an intense yellow colour with Cd(II) solution in basic medium. The maximum absorbance was observed at 440 nm, in basic buffer solution (pH 10.00). The molor absorptivity and Sandell’s sensitivity of Cd(II)-HBBrPT complex were 4035 mol-1cm-1and 0.02765 μg cm-2respectively. The stability constant of 1:2 Cd(II)-HBBrPT complex was 8.46×106. The effect of various iron was also studied.

scholarly journals SYNTHESIS OF NEW SUBSTITUTED PROCAINE HYDROCHLORIDE COMPOUNDS AND THEIR USE IN SPECTROPHOTOMETRIC DETERMINATION OF TETRACYCLINE HYDROCHLORIDE THROUGH DIAZOTIZATION-COUPLING REACTIONS

2021 ◽  
Vol 18 (39) ◽  
pp. 14-32
Author(s):  
Hind Sadiq Al-WARD ◽  
Mouayed Qassssim AL-ABACHI ◽  
Mohammed Rifaat AHMED
Keyword(s):  
Stability Constant ◽  
Thermodynamic Parameters ◽  
Coupling Reaction ◽  
Water Soluble ◽  
Procaine Hydrochloride ◽  
Effect Of Temperature ◽  
Basic Medium ◽  
Fast Method ◽  
The Stability

Background: Tetracycline is one of the most important antibiotics. It is used to treat many different bacterial infections. It is often used in treating severe acne, or sexually transmitted diseases such as syphilis, gonorrhea, or chlamydia. In some cases, tetracycline is used when penicillin or another antibiotic cannot be used to treat serious infections such as the ones caused by Bacillus anthracis, Listeria, Clostridium, Actinomyces. Aim: synthesized a new novel reagent used to determine TCH spectrophotometrically by using diazonium and coupling reaction. Methods: Four new substituted procaine derivatives were prepared by simple organic methods using aniline derivatives. A spectrophotometric approach was established for the micro-determination of TCH. The stoichiometry was investigated using mole ratio and continuous variation methods, and the stability constant was also estimated. The ΔG, ΔH, and ΔS were determined as thermodynamic parameters for evaluating the effect of temperature on the reaction. Results: Substituted procaine derivatives were prepared, and o-hydroxy procaine seems to be the best reagent used to determine TCH by diazotization and coupling reaction. The result was a yellow water-soluble dye with a maximum absorbance of 380 nm. The reaction conditions were studied and optimized. Beers law was obeyed over a concentration range (2.5–50) μg.mL-1 for TCH. The molar absorptivity was (14.4669.103) L.mol-1.cm-1, and the detection limit was (0.5052) μg.mL-1. The stoichiometry of the formed product was found 1:1 (o-hydroxyprocaine: TCH). The stability constant indicated that the product formed was stable, and the thermodynamic parameters showed that the diazonium salt reaction was preferred to occur at a low temperature. Conclusions: a simple, accurate, and fast method was developed to determine TCH in pure form and pharmaceuticals by coupling the TCH with a newly synthesized procaine derivative reagent (o-hydroxy procaine) in a basic medium.

scholarly journals EVALUASI PERLAKUAN AKUNTANSI ASET TETAP PADA CV SARANA ADI PUTRA PERIODE 2017 s/d 2018

2020 ◽  
Vol 12 (1) ◽  
pp. 95-104
Author(s):  
Fany Asmara ◽  
Yumniati Agustina
Keyword(s):  
Qualitative Methods ◽  
Purchase Price ◽  
Book Value ◽  
Line Method ◽  
Straight Line ◽  
Fixed Assets ◽  
Acquisition Costs ◽  
Straight Line Method ◽  
Descriptive Qualitative

The purpose of this study is to evaluate the accounting treatment of fixed assets in CV Sarana Adi Putra by using descriptive qualitative methods. This study refers to SAK ETAP Chapter 15 concerning fixed assets that apply in Indonesia. With the evaluation results of this study it can be concluded in terms of recognition of fixed assets are recognized if the fixed assets have been used as operational which is in accordance with SAK ETAP, and the acquisition of fixed assets is not in accordance with SAK ETAP because the company only records the purchase price, and costs incurred are directly charged . In terms of measurement of fixed assets, it is not in accordance with SAK ETAP because there is no policy governing the valuation. In terms of the methods of preparation, the company uses the straight-line method in accordance with SAK ETAP. In terms of the presentation of fixed assets, the company records acquisition costs, depreciation expense, accumulated depreciation, book value in which the accumulated depreciation is reduced according to SAK ETAP. in terms of disclosure of fixed assets, is not in accordance with SAK ETAP because there is no policy governing the disclosure.   Keywords: Fixed Assets, SAK ETAP Chapter 15 concerning Fixed Assets

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