A simplified collisional‐radiative model has been constructed for the system of the ground state, electronically excited stable states, and the ionic state of molecular hydrogen in plasma. Effective rate coefficients have been calculated for production of electrons, molecular ions, protons, and hydrogen atoms from molecular hydrogen. The ratio of the effective ionization rate of molecular hydrogen to the Balmer &agr; photon emission rate and the effective rate coefficients for radiation and energy losses are also presented. ©1995 American Institute of Physics.