  We derive the multi-component second-order dissipative relativistic
hydrodynamic equations using the moment-expansion method. By computing the
transport coefficients using hard-sphere interactions, we investigate the role
of multiple components and the reactive collisions. We find that both of these
factors increase the effective cross-section and hence decrease the transport
coefficients and relaxation times. We further compute such transport properties
using leading-order perturbative QCD cross-sections. For both types of
cross-sections, we find that the ratio between vector current relaxation time
and conductivity for a multi-component fluid is notably different from that for
a single-component fluid. Therefore, the current study provides a more
applicable guideline for such a ratio in phenomenological hydrodynamics
simulations.
