ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Spectrophotometric and conductometric studies of new synthesized azo derived from pyrazole as analytical reagents

F. A. El-Seify, F. I. El-Dossoki, and Mahmoud M. Gouda

Chemistry Department, Faculty of Engineering, Port Said University, Port Said, Egypt

E-mail: feldossoki64@sci.psu.edu.eg

Received: 12 April 2021  Accepted: 23 June 2021

Abstract:

A new pyrazole derivatives azo dye 1-(3-phenyl-5-Pyrazolylazo)-R acid (L₁) and 5-(3-phenyl-5-Pyrazolylazo)-8-hydroxy quinoline (L₂) was synthesized. The acid–base equilibrium, ionization constants, the effect of pH and some organic solvents on the spectra of ligands, the chromogenic reaction and the stability constant of Co⁺², Cu⁺²,Ni⁺² and Zn⁺² ion complexes with ligands were studied and determined spectrophotometrically and conductometrically. The optimum pH was determined for the ligands and the complexes. 2:1 and 1:1 (L:M) stoichiometric complexes have been formed in solutions. The stability constants order of the under study complexes was Co⁺² < Ni⁺² < Cu⁺². These metal ions were determined using the ligands as indicators. The reagents can be also useful to use as indicators in acid–base titrations as confirmed experimentally.

Keywords: Spectrophotometrically; Conductometrically; Pyrazole derivatives; Acid–base indicators

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-021-01753-1

Chemical Papers 75 (11) 5917–5927 (2021)