Mass Flux of Diffusion Component A in Heat and Mass Transfer Formulas

Yes, the Mass Flux of Diffusion Component A, measured in Mass Flux can be negative.

Mass Flux of Diffusion Component A is usually measured using the Kilogram per Second per Square Meter[kg/s/m²] for Mass Flux. Kilogram per Hour per Square Meter[kg/s/m²], Kilogram per Hour per Square Foot[kg/s/m²], Pound per Hour per Square Foot[kg/s/m²] are the few other units in which Mass Flux of Diffusion Component A can be measured.