Study of the kinetics of formation of a number of colored azo-chalcone dyes

The research included the kinetic study of the formation reactions for four Azochalcone dyes from the coupling reaction of four electron-donating chalcone with the diazotized para-aminobenzophenone reagent accepting these electrons at a temperature of (293K) and a neutral acidic function (pH7).The optimal conditions for each formed Azochalcone dye as well as the optimal ratios (Stoichiometric ratios) of its components were determined, which were (1:10) for (chalcone : diazotized reagent) respectively. Finally, the kinetics of the formation for the above dyes were followed spectrophotometrically, and it was found that these reactions are of the pseudo first order relative to chalcones, so we were able to calculate the rate constant (k1) and the half-life time (t1/2) for each reaction. And the highest value of the dye (3-(4-bromophenyl)-1-(4-nitrophenyl)prop-2-en-1-one with diazotized 4-aminobenzophenone reagent) was equal to (0.0601min.-1), that is, it is the fastest reaction. The lowest value of the dye (3-(4-hydroxyphenyl)-1-(4-nitrophenyl)prop-2-en-1-one with diazotized 4-aminobenzophenone reagent) was equal to (0.0472min.-1), while the values of the half-life time (t1/2) were completely opposite: (11.53) and (14.68). Minutes of the two produced dyes, respectively.