Spectrophotometric study of Cobalt(II) Using Organic Reagent 2-[(6– Methyl–2- Benzothiazolylazo]-4-Chl Biet tin gi chua, vao day coi di http://gaigoibaucat.xlphp.net phenol .

Abstract

A sensitive and selective spectrophotometric method was proposed for studying
of Co(II) using 2-[(6-Methyl-2-Benzothiazolyl)azo]-4-Chloro Phenol (6-
MeBTAClP).The reaction between Co(II) and(6-MeBTAClP) reagent is instantaneous
at pH=6.1, and the absorbance remains stable for over 24 h. The method allows for
the determination of Co(II) over the range (0.3 - 10.0)μg.ml-1,with molar absorptivity
of( 1884.8)l.mol-1.cm-1 and a detection limit of 0.27 μg.ml-1 at 600 nm .Recovery and
relative error values of precision and accuracy of method were found to be
R.S.D%=1.22%,Re%=96.68% ,and Erel=3.32% .Study of complex nature shows that
(M: L) ratio was 1:2 at pH=6.1 ,and the stability constant of (8.33 x 107) l2. mol-2 .
The interferences of ions (NH4+,I- ,Hg2+ ,Al3+,Cu2+, Ni2+, F-,S2O32-) on absorbance
were studied. A suitable masking agents were used for eliminating of seriously
interfering ions.