  We derive multicomponent relativistic second-order dissipative fluid dynamics
from the Boltzmann equations for a reactive mixture of $N_{\text{spec}}$
particle species with $N_q$ intrinsic quantum numbers (e.g. electric charge,
baryon number, and strangeness) using the method of moments. We obtain the
continuity equations for multiple conserved charges as well as the conservation
equations for the total energy and momentum in the single-fluid approximation.
These $4+N_q$ conservation laws are closed by deriving the second-order
equations of motion for the dissipative quantities in the $(10+4N_q)$-moment
approximation. The resulting fluid-dynamical equations are formally similar to
those of a single-component system, but feature different thermodynamic
relations and transport coefficients. We derive general relations for all
transport coefficients and compute them explicitly in the ultrarelativistic
limit.
