A liquid-phase chemical reaction A ! B takes place in a well-stirred tank. The concentration of A in the feed is C_A0 (mol/m₃), and that in the tank and outlet stream is CA (mol/m³). Neither concentration varies with time. The volume of the tank contents is V(m³) and the volumetric flow rate of the inlet and outlet streams is V(m³/s). The reaction rate (the rate at which A is consumed by reaction in the tank) is given by the expression 

(a) Is this process continuous, batch, or semibatch? Is it transient or steady-state? 

(b) What would you expect the reactant concentration C_A to equal if k = 0 (no reaction)? What should it approach if k → ∞ (infinitely rapid reaction)? 

(c) Write a differential balance on A, stating which terms in the general balance equation (accumulation = input + generation - output - consumption) you discarded and why you discarded them. Use the balance to derive the following relation between the inlet and outlet reactant concentrations:

Verify that this relation predicts the results in Part (b).

Transcribed Image Text:

r(mol A consumed/s) = KVCA where k is a constant. V(m'/s) CAo(mol/m) V(m) CA(mol/m)