An interpretive concept has recently been published to rationalize the changes generated by the change of control parameters (pressure, temperature, composition) in complex equilibrium systems. It was proven that all of the sensitivity coefficients (and many other thermodynamically important quantities) may be split into terms which are uniquely assigned to the so-called response reactions (RERs). RERs were defined by the missing species and their derivation was based on the stoichiometrically independent reactions (SIRs). In this paper we redefine RERs with the help of the participating species and derive them from the composition of the participating species. This new way of definition and derivation leads to the classification of RERs, which was not possible before and helps to understand the underlying chemistry of governing and regulating the equilibrium systems. The formulae are presented in general form, but some examples are also given to rationalize their meaning.