In this paper, we will study the chaotic behaviour, in the sense of Devaney, of infinite-dimensional linear systems on Banach spaces, especially we will study the solution $C_0$-semigroups of operators of these systems. We will focus on the models of kinetic theory as is the case of the birth-and-death models. Azmy and Protopopescu studied these processes for the first time. In addition, this subject has been intensively studied by Banasiak, Lachowicz and Moszynski.