SPECTROPHOTOMETRIC STUDY OF ACID-BASE EQUILIBRIA OF 4-(2-BENZOTHIAZOLYLAZO)RESORCINOL AND 4-(2-BENZOTHIAZOLYLAZO)SALICYCLIC ACID

Authors
ABUBAKR MS ELSHAHAWY AS AHMED SM
Citation
Ms. Abubakr et al., SPECTROPHOTOMETRIC STUDY OF ACID-BASE EQUILIBRIA OF 4-(2-BENZOTHIAZOLYLAZO)RESORCINOL AND 4-(2-BENZOTHIAZOLYLAZO)SALICYCLIC ACID, Indian journal of chemistry. Sect. A: Inorganic, physical, theoretical & analytical, 32(9), 1993, pp. 789-793
Citations number
19
Categorie Soggetti
Chemistry
Journal title
Indian journal of chemistry. Sect. A: Inorganic, physical, theoretical & analytical → ACNP
ISSN journal
03764710
Volume
32
Issue
9
Year of publication
1993
Pages
789 - 793
Database
ISI
SICI code
0376-4710(1993)32:9<789:SSOAEO>2.0.ZU;2-L
Abstract
The visible absorption spectra of 4-(2-benzothiazolylazo)resorcinol an d 4-(2-benzothiazolylazo)salicyclic acid have been recorded in aquo-or ganic solvent mixtures in the pH range 0.5-12.0. The spectral changes have been explained in terms of shifts in equilibria amongst different molecular and ionic species of BTAR and BTAS existing in solution. Th e pK(a) values corresponding to the different ionisation steps have be en determined at 25-degrees-C and I = 0.1 M (KNO3) by graphical analys is of the absorbance-pH curves.