Spectrophotometric Determination of Sm(III) Content in Hydrochloric Acid Solution

2003 ◽  
Vol 70 (5) ◽  
pp. 729-732
Author(s):  
N. N. Kostyuk ◽  
T. A. Dik ◽  
A. G. Trebnikov
Keyword(s):  
Hydrochloric Acid ◽  
Acid Solution ◽  
Spectrophotometric Determination ◽  
Hydrochloric Acid Solution

Determination of p-Aminobenzoic Acid in Feeds

1964 ◽  
Vol 47 (2) ◽  
pp. 214-218
Author(s):  
Richard T Merwin
Keyword(s):  
Hydrochloric Acid ◽  
Acid Solution ◽  
Hydrochloric Acid Solution ◽  
Alkaline Hydrolysis ◽  
Spectrophotometric Assay ◽  
Aminobenzoic Acid ◽  
Drug Content ◽  
Collaborative Studies ◽  
Qualitative Test

Abstract Collaborative studies were conducted on a revised method for p-aminobenzoic acid (PABA) in feeds. PABA is diazotized and coupled with N-1-naphthylethylenediamine dihydrochloride to form a red complex that provides both a qualitative test and a spectrophotometric assay. The PABA is extracted with a 10% hydrochloric acid solution and the alkaline hydrolysis step is eliminated. Results were close to the labeled drug content, although the aged feed evidenced drug instability. The revised method is recommended for adoption as official, first action.

Selective determination of tantalum in ores by extraction with N-phenylbenzohydroxamic acid in toluene

1990 ◽  
Vol 55 (7) ◽  
pp. 1686-1690 ◽  
Author(s):  
José Aznarez ◽  
Juan Carlos Vidal ◽  
Cecilia Vaquero
Keyword(s):  
Hydrochloric Acid ◽  
Acid Solution ◽  
Aqueous Phase ◽  
Spectrophotometric Determination ◽  
Absorption Maximum ◽  
Good Accuracy ◽  
Molar Absorptivity ◽  
Selective Determination ◽  
Accuracy And Precision

A method for tantalum(V) spectrophotometric determination in a non-aqueous phase is proposed. Tantalum(V) is extracted with N-phenylbenzohydroxamic acid into toluene from a 5M hydrochloric acid solution. The colour is then developed by addition of 4-(2-pyridylazo)-resorcinol (PAR) solution in N,N-dimethylformamide and pyridine to an aliquot of the extracted phase. The Ta(V)-PAR complex gives an absorption maximum at 547 nm with a molar absorptivity of 3.88 ± 0.04 . 104 l mol-1 cm-1. The method has been applied to the selective determination of tantalum in ores with good accuracy and precision.

Sign in / Sign up

Export Citation Format

Share Document