  Co-existence of phase segregation and \emph{interconversion} or
\emph{isomerization} reaction among molecular species leads to fascinating
structure formation in biological and chemical world. Using Monte Carlo
simulations of the prototype Ising model, we explore the chemical kinetics of
such a system consisting of a binary mixture of \emph{isomers}. Our results
reveal that even though the two concerned processes are individually Arrhenius
in nature, the Arrhenius behavior of the \emph{isomerization} reaction gets
significantly disrupted due to an interplay of the nonconserved dynamics of the
reaction and the conserved diffusive dynamics of phase segregation. The
approach used here can be potentially adapted to understand reaction kinetics
of more complex reactions.
