The comparison of two methods used to observe a nonlinear system: potentiometry and holography

Marina Simović Pavlović,University Of Belgrade, Faculty Of Mechanical Engineering, Serbia ,University Of Belgrade, Institute Of Chemistry, Technology And Metallurgy, Serbia ,Maja Pagnacco,Jelena Maksimović,Tijana Maksimović,3University Of Belgrade, Faculty Of Physical Chemistry, Serbia ,University Of Kragujevac, Faculty Of Science, Serbia

doi:10.46793/iccbi23.164sp

Abstract

The transition from state I (characterized by low iodide and iodine concentration) to state II (high iodide and iodine concentration) occurs in a nonlinear Briggs-Rauscher (BR) oscillatory reaction. This transition was studied by two methods: potentiometric and holographic. The first derivative technique was applied to the obtained electrochemical and holographic curves of the transition state I→state II to obtain the corresponding slopes. Based on these slopes, the results of the two methods are compared. The obtained holographic slope for the transition from state I to state II is higher than the potentiometric one in all selected reaction sections. In the initial phase of the transition from state I to state II, it is clear that the velocity of the holographic method is twice that of the potentiometric method. While this trend shows a twofold increase at the beginning of the phase transition, it deviates in the other phases, where the holographic measurements show a 1.5-fold higher rate in the middle. The obtained results could have a strong impact on the study of nonlinear systems in the future.

Full Text