In this paper, a new class of generalized separation axioms (briefly, g-Tg-separation axioms) whose elements are called g-T g,K , g-T g,F , g-T g,H , g-T g,R , g-T g,N -axioms is defined in terms of generalized sets (briefly, g-Tg-sets) in generalized topological spaces (briefly, Tg-spaces) and the properties and characterizations of a Tg-space endowed with each such g-T g,K , g-T g,F , g-T g,H , g-T g,R , g-T g,N -axioms are discussed. The study shows that g-T g,F -axiom implies g-T g,K -axiom, g-T g,H -axiom implies g-T g,F -axiom, g-T g,R -axiom implies g-T g,H -axiom, and g-T g,N -axiom implies g-T g,R -axiom. Considering the T g,K , T g,F , T g,H , T g,R , T g,N -axioms as their analogues but defined in terms of corresponding elements belonging to the class of open, closed, semi-open, semiclosed, preopen, preclosed, semi-preopen, and semi-preclosed sets, the study also shows that the statement Tg,α-axiom implies g-T g,α -axiom holds for each α ∈ {K, F, H, R, N}. Diagrams expose the various implications amongst the classes presented here and in the literature, and a nice application supports the overall theory.