화학공학소재연구정보센터
Indian Journal of Chemical Technology, Vol.10, No.3, 295-297, 2003
Determination of silver at submicrogram levels by absorption spectrophotometry
A selective and sensitive spectrophotometric method is described for the determination of 15-700 ng of Ag(I). Silver is extracted as silver iodide into benzene and selectively stripped into ammonia. The iodide associated with silver in the ammonical stripping is oxidised to iodate and then treated with excess iodide to give iodine. The iodine formed is extracted into benzene and equilibrated with iodate in acidic medium in the presence of chloride and Rhodamine 6G for the formation of ICl2- Rh 6G(+) ion-pair in benzene layer. Determination is completed by measuring the absorbance of the extract at 535 nm. The coefficient of variation is 1% for 10 determinations of 630 ng of silver. The method has been applied to establish,the. silver content of dental samples, ornamental washing and photographic sample.