Question regarding units of an equation For a university project, I need to use the following equations, but I am having difficulty with the units of the term of the left-hand side (ΔXh). As far as I understand it, the units of this term should be µgCOD/(litre*hour), but I cannot see how that is the case. Perhaps I just have the units of one of the right-hand side terms incorrect? ΔXh = Yh*(1 - kuap - keps)*Ubom*Xh Units: Yh [µgCOD/µgCOD] kuap [µgCOD/µgCOD] keps [µgCOD/µgCOD] Ubom [µgCOD/(litre*hour)] Xh [µgCOD/litre] where µgCOD = micograms of chemical oxygen demand (a mass unit) Thanks in advance for any help!

Isn't this your equation?: $\frac{\operatorname{d} X_h}{\operatorname{d} t} = Y_h\cdot (1 - k_{UAP} - k_{EPS})\cdot U_{BOM}\cdot X_h$

Units:

$X_h [\mu gCOD]$ concentration of biomass (heterotroph)

$Y_h [\mu gCOD/\mu gCOD_x]$ true yield coefficient (heterotroph)

$k_{UAP} [\mu gCOD/\mu gCOD_x]$ UAP formation rate constant

$k_{EPS} [\mu gCOD/\mu gCOD_x]$ EPS formation rate constant

$U_{BOM} [\mu gCOD/(\mu gCOD_x\cdot L\cdot Hr)]$ utilisation rate of biological organic matter