Inhomogeneity After Mixing Solutions: Chemical Wave Pattern in the Belousov-Zhabotinsky Reaction

Video: https://youtu.be/Hs8zH2E9LqU

Behaviour of Chemical Wave at Different Stop Times (n)

Experimental results: (A) upward chemical wave, (B) complicated pattern, and (C) global-oscillation-like pattern. The speed was 200 times faster than the real speed.

The BZ reaction is a nonlinear chemical reaction that shows period oscillations in the concentration of the reaction intermediates. A significant characteristic of the BZ reaction is the amplification of a small initial concentration fluctuation in the excitable system. The oscillation period depends on the stirring rate in the batch reactor; with increasing stirring rate, the period increases and the oscillation suddenly disappears

After the completion of the mixing between BZ and ferroin solutions with the rotation-and-stop method, three modes were observed for different values of n. The first was an upward chemical wave.

This type of pattern is likely to appear at relatively smaller n values. This upward chemical wave was generated at the bottom of the solution, then travelled upward and spread in the entire solution.

The second pattern was referred to as the complicated pattern. In this pattern, a chemical wave was generated at the top or middle of the solution together with an upward chemical wave or oscillation at the local place. This complicated pattern observed 30 min after the rotation-and-stop process, was transient, and one of the local chemical waves or chemical oscillations became dominant over time.

The last pattern was a global-oscillation-like pattern over the entire solution. In this phenomenon, the colour of the entire solution oscillated for at least 30 min after the completion of the rotation-and-stop process. This oscillation is gradually transformed into a one-dimensional chemical wave (primarily into an upward wave) over time.

Keywords: Belousov-Zhabotinsky reaction, mixing, chemical oscillation, chemical wave, visualization, nonlinear dynamics, inhomogeneity

Citation: Okamoto Y, Okita E, Yamamoto D, Nakata S and Shioi A (2022) Detection of Inhomogeneity After Mixing Solutions by Analyzing the Chemical Wave Pattern in the Belousov-Zhabotinsky Reaction. Front. Phys. 10:895824. doi: https://doi.org/10.3389/fphy.2022.895824

Received: 14 March 2022; Accepted: 07 April 2022;

Published: 04 May 2022.

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