Author/Authors :
Froudi Jahromi, Mohammad Reza Chemistry Department - Dashtestan Branch - Islamic Azad University, Dashtestan, Iran , Zandifar, Samira Chemistry Department - Dashtestan Branch - Islamic Azad University, Dashtestan, Iran , Pakdaman, Ehsan Chemistry Department - Islamic Azad University - Kangan branch, Kangan, Iran , Tavakoli, Fatemeh Chemistry Department - Islamic Azad University - Kangan branch, Kangan, Iran , Bagheri, Saideh Young Researchers and Elite Club - Shiraz Branch - Islamic Azad University, Shiraz, Iran
Abstract :
A new kinetic spectrophotometic method for the determination of trace amount Chromium (III) in Tea
real samples has been described based on it s the catalytic effect on the oxidations of 1 - ( 2 –
PyridylAzo ) - 2 - Naphthol, (PAN), by potassium bromated in sulfuric acid. The reaction is followed
spec- trophotometrically by measuring the decrease in the absorbance at 469 nm. Under the optimum
conditions of0.2 molL-1 sulfuric acid, 1.0 × 10-4 molL-1, 1- ( 2 -PyridylAzo ) - 2 - Naphthol, (PAN),
0.01 molL-1 potassium bromate at 35oC, calibration graph in the rang of 0.001-0.06 ngL-1 Chromium
(III). Concentration was obtained with detection limit of 0.2303 g mL-1 by the fixed-time method of
5.5 min. The relative standard deviation for 0.05AngL-1 Chromium (III) is %90. No serious interference
was identified. The applicability of the method was demonstrated by the determination of the
Chromium (III) in Water, Vegetables and blood samples.
Keywords :
kinetic , Spectrophotometic , PAN , Determination , Chromium (III)