[en] The single species neutral - shielding model for the ablation of a hydrogenic pellet is extended by considering the ablatant as a mixture of four species: Molecular and atomic hydrogen, protons and electrons. Compared with the single-species-ablatant model, results of the analysis showed that the ablatant state differs considerably. The attenuation of the incoming electron energy and energy flux, however, are very much similar, irrespective of the ablatant composition. The scaling law of the pellet ablation rate with respect to the plasma state of T_e, n_e and the pellet radius, r_p remains the same; the ablation rate is reduced approximately by 15%. At some combinations of T_e, n_e and r_p, a weak shock can appear when the ablated flow downstream becomes sonic. A sufficient but not necessary condition for its occurrence is that the ablatant approaches either a state of complete dissociation, or complete ionization. To study the possible existence of an effective energy absorbing spherical region around the pellet, a comparison between the local ablated electron collisional mean free path and the electron Larmor radius in the cloud is made. A critical field, B_c is then defined and evalued at the ionization radius, r_i. For plasma state of fusion interest and pellet radius beyond 0.15 mm, B_c is well above 10 Tesla. (orig.) With 3 tabs., 7 figs., 21 refs