Related Experiment Video
Updated: Apr 11, 2026

Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
Determination of Cr and Ni in Orujo spirit samples by ETAAS using different chemical modifiers
M Vilar Fariñas1, J Barciela García1, S García Martín1
1Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo, Spain.
Abstract:
Several analytical methods are proposed for chromium and nickel determination in Orujo spirit samples using ETAAS. Permanent chemical modifiers such as W, Ir, Ru, W-Ir and W-Ru were comparatively studied in relation to the common chemical modifier employed, Pd(NO3)2-Mg(NO3)2. Taking into account the analytical performance, the method based on the use of Ru as a permanent modifier was selected for further direct Cr determinations in Orujo samples. In the case of Ni, after comparison among the different methods developed, a method with no modifier which allows the direct interpolation in calibration graphs was chosen. Detection limits of 0.13μgL(-1) and 0.30μgL(-1) were obtained for Cr and Ni, respectively. For all methods developed, recoveries (ranged 98.6-102%) and precision (RSD<10%) were acceptable. The selected methods were applied for the determination of the Cr and Ni contents in 80 representative Orujo Galician samples. The Cr concentrations ranged from
More Related Videos
Related Concept Videos
EDTA: Indirect and Alkalimetric Titration
Experimental Determination of Chemical Formula
Effects of EDTA on End-Point Detection Methods
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a...
Precipitation Titration: Endpoint Detection Methods
In the Volhard method, a standard excess of AgNO3 is first added to the...
EDTA: Direct, Back-, and Displacement Titration
Direct titration involves buffering the metal ion solution to the desired pH and directly titrating with standard EDTA until the endpoint. The optimum pH ensures a large conditional formation constant of metal−EDTA and visibility of the free indicator color in the solution. In addition, auxiliary complexing reagents are used to prevent the precipitation of metal hydroxides...
Qualitative Analysis
For instance, group IV...

