It says d(C_A* V)/dt = (C_a,in)Q_in - (C_a)Q + (r_A)V
"r" is defined as r = -kC_A.
I think you answered your own question.
is defined as the rate of formation of A per unit volume. The equation for rA
depends on the nature of the chemical reaction.
The dynamic material balance for species A in a CSTR is given by:
is the volume of the CSTR
is the concentration of A in the feed stream
3. F refers to the flowrate.
For an irreversible chemical reaction A -> B + C, rA
= - rate of consumption of A = -k.CA
since A is being consumed by the reaction.
For a reversible chemical reaction, A <-> B + C, rA
= rate of generation - rate of consumption = kb