Acid-Base Equilibria in Glacial Acetic Acid. I. Spectrophotometric Determination of Acid and Base Strengths and of Some Dissociation Constants1

Abstract Chlorophacinone and diphacinone are extracted at the 0.005% level from grain or paraffinized baits with glacial acetic acid. The target concentration is 0.01 mg/mL. The filtered supernate is chromatographed on a Partisil PXS ODS10/25 liquid chromatography column with premixed and degassed glacial acetic acid-tetrahydrofuran-water (14 + 2 + 9) and detected at 288 nm. The concentration is calculated by using an external standard. The recovery from spiked samples averaged 96.6% for both analytes. The response is linear from 0.001 to 0.040 mg/mL. The coefficient of variation of within-day replicates ranged from 1.1 to 2.5%.

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Extraction and Spectrophotometry Determination of Benzthiazide, Hydrochlorothiazide, and Hydroflumethiazide in Pharmaceuticals

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/53.3.582 ◽

1970 ◽

Vol 53 (3) ◽

pp. 582-584

Author(s):

F Raymond Fazzari

Keyword(s):

Acetic Acid ◽

Spectrophotometric Determination ◽

Organic Phase ◽

Active Ingredient ◽

Separation Techniques

Abstract A method has been developed for the determination of benzthiazide, hydrochlorothiazide, and hydroflumethiazide in pharmaceuticals. The procedure is rapid and specific and employs established separation techniques. The active ingredient is eluted from a basic Celite column with an acetic acid-ether solvent and extracted from the organic phase into NaOH for the spectrophotometric determination.

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Spectrophotometric determination of bismuth with diethylenetriaminepenta-acetic acid

Talanta ◽

10.1016/0039-9140(78)80173-8 ◽

1978 ◽

Vol 25 (11-12) ◽

pp. 691-692 ◽

Cited By ~ 2

Author(s):

P. Nenova ◽

D. Kantcheva ◽

B. Karadakov

Keyword(s):

Acetic Acid ◽

Spectrophotometric Determination

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ChemInform Abstract: DETERMINATION OF THE OVERALL DISSOCIATION CONSTANTS OF THE GROUP 1A ACETATES AND PERCHLORATES IN GLACIAL ACETIC ACID

Chemischer Informationsdienst ◽

10.1002/chin.198145092 ◽

1981 ◽

Vol 12 (45) ◽

Author(s):

C. M. TANG ◽

J. A. JUN. MCLEAN

Keyword(s):

Acetic Acid ◽

Glacial Acetic Acid ◽

Dissociation Constants

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TLC Separation and Spectrophotometric Determination of 2-Aminoanthraquinone in D&C Blue No. 9

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/52.4.831 ◽

1969 ◽

Vol 52 (4) ◽

pp. 831-832

Author(s):

Sandra J Bell

Keyword(s):

Acetic Acid ◽

Thin Layer ◽

Spectrophotometric Determination ◽

Diethyl Ether ◽

Thin Layer Plate ◽

Color Additive ◽

Tlc Separation

Abstract Batches of 3,3’-dichloroindanthrene meeting the specifications set forth in the Color Additive Regulations are certifiable as D&C Blue No. 9. One of the specifications requires that D&C Blue No. 9 contain no more than 0.2% 2-aminoanthraquinone. In the method described, 2-aminoanthraquinone is extracted from D&C Blue No. 9 with dimethylsulfoxide, together with several other impurities. This solution is spotted onto a thin layer plate and developed with diethyl ether. After removal from t he plate, the 2-aminoanthraquinone is extracted into acetic acid and the amount is determined spectrophotometrically. Recoveries of 0.1, 0.2, and 0.5% of added intermediate ranged from 86 to 96%.

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Method for the accurate determination of specific rotation. Specific rotation of valine and leucine

Canadian Journal of Chemistry ◽

10.1139/v69-456 ◽

1969 ◽

Vol 47 (15) ◽

pp. 2739-2746 ◽

Cited By ~ 1

Author(s):

J. C. MacDonald

Keyword(s):

Acetic Acid ◽

Glacial Acetic Acid ◽

Optical Rotation ◽

Accurate Determination ◽

Computer Calculation ◽

Specific Rotation ◽

Best Fit

The optical rotation of various concentrations of L-valine and L-leucine, dissolved in glacial acetic acid, or 5 or 6 M HCl, was measured with a photoelectric polarimeter at the nominal wavelengths 589, 578, 546, 436, and 365 nm and temperatures of 20, 25, and 30 °C. The specific rotation for any one wavelength, solute, and solvent could be defined by the equation [α]λT = A(1 + D(T − 25)) + BC, where T is temperature in °C, C is concentration in grams of solute per 100 ml of solution, and A, B, and D are constants. The best fit values of the constants were determined by computer calculation and are listed. Constants are also given for calculating a specific rotation based on grams of solute per 100 g of solution.

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