Ionic plasma coupling parameter, Γ_i, illustrated for three models with varying masses at Z = 0.02. The upper panel shows Γ_i as a function of the fractional radius, while the lower panel shows Γ_i as a function of temperature (log T). Regions with higher values of Γ_i indicate a greater influence of electrostatic effects within the stellar interior. Across these three models, the significance of Coulomb effects is more pronounced in the outer stellar layers. The helium ionization zones are indicated with a purple double arrow, where the plasma coupling parameter reaches its maximum value. Additionally, three regions of equal length in radius are shown: Region A corresponds to the innermost third of the model, Region B to the central third, and Region C to the outermost third of the stellar interior. In all the plots, light blue regions correspond to radiative zones, and light red regions to convective regions. Finally, all three models in this figure are at IAMS, meaning they are in the middle of their evolutionary path on the MS.