  We derive self-consistent formalism for the description of multi-component
partially ionized solar plasma, by means of the coupled equations for the
charged and neutral components for an arbitrary number of chemical species, and
the radiation field. All approximations and assumptions are carefully
considered. Generalized Ohm's law is derived for the single-fluid and two-fluid
formalism. Our approach is analytical with some order-of-magnitude support
calculations. After general equations are developed we particularize to some
frequently considered cases as for the interaction of matter and radiation.
