Question

There are 5 tanks connected in series. If the average residence time is 5 sec, first order rate constant is 0.5 sec^-1, the initial concentration is 5\(\frac{mol}{m^3},\) then the conversion at the exit of 5^th reactor in (\(\frac{mol}{m^3}\)) is ____

(a) 0.34

(b) 0.51

(c) 0.65

(d) 0.81

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This interesting question is from Tanks in Series Model in portion Compartment Models, Models for Non Ideal Reactors of Chemical Reaction Engineering

Answer 1

The correct answer is (c) 0.65

The best explanation: CN = C0 \(\frac{1}{(1+\frac{τk}{N})^N} \)

CN = 5×\(\frac{1}{(1+\frac{5×0.5}{5})^5}  \)

CN = 0.65\(\frac{mol}{m^3}. \)