CKRCXP    CKRCXP    CKRCXP    CKRCXP    CKRCXP    CKRCXP    CKRCXP    
          **********************************************
                    **************************
                              ******

SUBROUTINE CKRCXP  (P, T, X, ICKWRK, RCKWRK, RCFT, RCRT)
Returns the forward and reverse rate constants for all reactions
given pressure, temperature and mole fractions.
Note this subroutine will calculate a value for the reverse rate
constant irrespective of whether the reaction was deemed reversible
in the interpreter file.  Also note that the concentration of third
bodies for third body reactions is included in the returned rate
constant.  The units for the rate constant will depend
on the number of reactants.

INPUT
P      - Pressure.
              cgs units - dynes/cm**2
              Data type - real scalar
T(*)   - Temperature.
              cgs units - K
              Data type - real array
X      - Mole fractions of the species.
              cgs units - none
              Data type - real array
              Dimension X(*) at least KK, the total number of
              species.
ICKWRK - Array of integer workspace.
              Data type - integer array
              Dimension ICKWRK(*) at least LENIWK.
RCKWRK - Array of real work space.
              Data type - real array
              Dimension RCKWRK(*) at least LENRWK.

OUTPUT
RCFT      - Rate constant for the forward reaction.
              cgs units - mole/(cm**3*sec) *
                      (cm**3/mole)**(sum of forward stoich. coeff)
              Data type - real array
              Dimension RCFT(*) at least II, the total number
              of reactions.
RCRT      - Rate constant for the forward reaction.
              cgs units - mole/(cm**3*sec) *
                      (cm**3/mole)**(sum of reverse stoich. coeff)
              Data type - real array
              Dimension RCRT(*) at least II, the total number
              of reactions.