Synthesis, Characterization and Thermal Decomposition Kinetics of Some Azo Dye Complexes of Chromium(III)

Abstract

Chromium(III) complexes of 2,3-dimethyl-1-phenyl-4-(2-hydroxy-
naphthylazo)-5-pyrazolone; 2,3-dimethyl-1-phenyl-4-(2,4-dihydroxy-
phenylazo)-5-pyrazolone and 2,3-dimethyl-1-phenyl-4-(2-
hydroxy-5-methylphenylazo)-5-pyrazolone have been synthesised
and characterised on the basis of elemental analysis, molar conductance,
magnetic susceptibility measurements, infrared and electronic
spectral studies. Thermal decomposition kinetics of these complexes
in nitrogen atmosphere was investigated by TG and DTG techniques.
Kinetic parameters such as activation energy E, pre-exponential
factor A and entropy of activation  ΔS were calculated.