Problem $02$:

The following first$-$order liquid phase reaction is carried out in an isothermal PFR as follows:

$AB,k=0\mathrm{.}5mi{n}^{-1}$

If $95\%$ of $A$ is converted to $B$ in the PFR:

a$)$ Determine the minimum number of identical CSTRs in series $($with the same total volume as the

original PFR$)$ required to get within $95\%$ of this conversion?

b$)$ Determine the minimum number of identical CSTRs in series $($with the same total volume as the

original PFR$)$ required to get within $99\%$ of this conversion?

c$)$ Does this make sense? Why are the answers to $($a$)$ and $($b$)$ so different?