  We study the properties of a steady, multi-species, low angular momentum
accretion flow around a Schwarzschild black hole. Each species is described by
a relativistic equation of state. We find that the transonic properties depend
strongly on the composition of the flow. We find that an electron-positron pair
plasma is the least relativistic one. This flow produces only one sonic point
very close to the event horizon and does not show multiple critical points for
any angular momentum or energy. When the baryons are present, the number of
critical points depend on the specific energy content. Since the number of
critical points decide whether the flow will have non-linearities or shock
waves, our results implies that whether or not standing shocks forms will
depend on the flow composition. Thus, for instance, a pure electron-positron
pair plasma will never undergo a shock transition, while mixing it with some
baryons (common in outflows and jets, for example) as in a completely ionized
gas, will have shocks. We study in detail how the baryon loading affects the
shock properties and discuss implication in astrophysical observations.
