We investigated the effect of superelastic electronic collisions of electrons, with the c (3)Pi(u) state of the H-2 molecule, on the electron energy distribution function (eedf) of a de positive column. We use a recently calculated set of electronic superelastic collision cross-sections [C.S. Sartori, F.J. da Paixao, M.A.P. Lima, Phys. Rev. A 55 (1997) 3243] to study the effect of these collisions on the eedf, the transport parameters, ionization and dissociation rates. We include two possible pathways, c (3)Pi(u) --> b (3)Sigma(u)(+) and c (3)Pi(u) --> X (1)Sigma(g)(+), for superelastic collisions of electrons with molecules in the metastable state. Cross-sections of the order of 10(-14) cm(2) at low energy enhance the eedf tail by superelastic electronic collisions, in particular for low reduced electric field E/N. This result changes considerably the dissociation and ionization rates by six orders of magnitude in the region from 10 to 50 Td. (C) 1999 Elsevier Science B.V. All rights reserved.24641699275282