Related Experiment Video
Updated: May 30, 2026

Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
Published on: February 20, 2020
Complex kinetics and significant influences of bromine removal in ferroin-bromate-metol reaction
1Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON N9B 3P4, Canada.
Abstract:
This study presents a new bromate-based chemical oscillator that employs metol as the organic substrate. Complex reaction behaviors were observed when the system was subjected to bromine removal and oxygen exposure. Transitions from simple to sequential oscillations took place as a function of the age of the metol stock solution. MS spectroscopy measurements and parallel kinetic experiments with a mixture of metol and hydroquinone suggest that the decomposition of metol to hydroquinone was responsible for the observed influence of oxygen and the age of the metol solution. GS/MS and NMR measurements revealed that 1,4-benzoquinone and bromobenzoquinones were the major final products, regardless of the presence of oxygen and bromine removal. Preliminary exploration in a capillary tube showed some interesting propagating pulse behavior.
Related Concept Videos
Electrophilic Aromatic Substitution: Chlorination and Bromination of Benzene
Rate-Determining Steps
In a multistep reaction mechanism, one of the elementary steps progresses significantly slower than the others. This slowest step is called the rate-limiting step (or rate-determining step). A reaction cannot proceed faster than its slowest step, and hence, the rate-determining step limits the overall reaction rate.
The concept of rate-determining step can be understood from the analogy of a 4-lane freeway with a short-stretch of traffic-bottleneck caused due to...
Chain Reactions
Halogenation of Alkenes
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
Structure of Benzene: Kekulé Model
He proposed that benzene has a cyclic structure of six carbon atoms attached to one hydrogen atom each, with three alternating pi bonds.
Radical Substitution: Allylic Bromination

