Second order consecutive irreversible reaction as shown in the bellow
figure, were carried out in a constant volume isothermal batch reactor with
different initial feed compositions. Reactor temperature was same in all the
cases. In experiments where the ratio of concentration of B to that of A in
the initial feed was less than 0.5, the concentration of B increased first,
reached a maximum and then declined with time. However, for all
experiments where this concentration ratio was 0.5 or above, concentration
of B decreased monotonically with time right from the beginning. What is
the ratio of the two rate constants (k1
/k2
)?
(A) 1/4
(B) 1/2
(C) 2
(D) 4

1 Answer

Answer :

(A) 1/4

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