دراسة معقد الحديد الثلاثي مع حمض '2، '3-دي هيدروكسي-'5- نترو-آزوبنزن-4-سلفونيك و استخدامه كمشعر لمعايرات التعقيد في المحاليل المائية

Abstract EN

Study the analytical properties of the complex of the ferric ions with 2’,3’-Dihydroxi - 5’- nitro azobenzene - 4- sulfonic acid and using it as a new indicator for photometric complexmetric titration in aqueous solutions is the aim of this research.

The molar absorptivity of the formed complex when 2',3'- Dihydroxi - 5’-nitro azobenzene - 4- sulfonic acid reacts with ferric ions at Xmax=650 nm was £xmax=4312.5±112.5 L.mol"1.cm"1 , and the calculated stability constant of this complex was (logP = 16.648 ± 0 .

1 7 8).

The stability constant of the formed complex is smaller than the stability constant of the complex FeY" - Iron (III) ions - EDTA , and therefore 2',3'- Dihydroxi - 5’- nitro azobenzene - 4- sulfonic acid is considered an ideal indicator for determinetion of ferric ions.

The optimal pH ranged between 1.9-2.85 where the complex completely formed