Vol.1, No 4, 1997 pp. 35 - 40
UDC: 543.23
KINETIC DETERMINATION OF ULTRAMICRO AMOUNTS OF Co(II)
Aleksandar R. Igov, Ranko M. Simonović1, Rangel P. Igov2
"Ratko Pavlović"-NITEX Niš, Yugoslavia
1 Faculty of Science, University of Priština, Yugoslavia
2 Faculty of Philosophy, University of Niš, Yugoslavia
Abstract. A new catalytuc reaction was proposed and a kinetic method was developed for the determination of ultramicro amounts of Co(II) in solution, based on its catalytic effect in the oxidation of the 4-hydroxycoumarinil-3-sulphonaminoacetic acid by KMnO4 in acetate buffer. The sensitivity of the method is 0.25 ng/cm3 Co(II).
The probably relative error ranges between 2.5 and 10.9% for concentration interval 4.0 to 0.5 ng/cm3 Co(II). Kinetic equations were proposed for the investigated process. The effects of certain foreign ions upon the reaction rate were determined for the assesment of the selectivity of the method.
Key words: cobalt, kinetic determination, 4-hydroxycoumarinil-3-sulpho-n-ami-noacetic acid 
KINETIČKO ODREĐIVANJE ULTRAMIKRO KOLIČINA Co(II)
Predložena je nova katalitička reakcija i razrađena kinetička metoda za određivanje ultramikro količina Co(II) u rastvoru na osnovu njegove katalitičke aktivnosti pri oksidaciji 4-hidroksikumarinil-3-sulfonaminosirćetne kiseline sa KMnO4 u acetatnom puferu. Osetljivost metode iznosi 0,25 ng/cm3 Co(II). Verovatna relativna greška se kreće od 2,5 do 10,9% za interval koncentracija od 4,0 do 0,5 ng/cm3 Co(II). Predložene su kinetičke jednačine za proučavani proces. Radi ocene selektivnosti metode ispitan je uticaj izvesnog broja stranih jona na brzinu reakcije.
Ključne reči: kobalt, kinetičko odredjivanje,4-hidroksikumarinil-3-sulfonamino/sirćetna kiselina