Chemical Reaction Engineering GATE-2021
Q 1: Ethylene adsorbs on the vacant active sites V of a transition metal catalyst according to the following mechanism.
C_2H_4+2V\rightleftharpoons V\cdots C_2H_4\cdots VIf NT, NV, and N_{C_2H_4} denote the total number of active sites, number of vacant active sites, and number of adsorbed C2H4 molecules, respectively, the balance on the total number of active sites is given by
Q 2: The following homogeneous liquid phase reactions are at equilibrium.
The values of rate constants are given by: k1 = 0.1 s–1, k–1 = 0.2 s–1, k2 = 1 s–1, k–2 = 10 s–1, k3 = 10 s–1. The value of rate constant k–3 is ___________ s–1 (round off to 1 decimal place).
Q 3: The following isothermal autocatalytic reaction,
A+B\rightarrow2B;\;(-r_A)=0.1C_AC_B(mol\;L^{-1}\;s^{-1})Is carried out in an ideal continuous stirred tank reactor (CSTR) operating at a steady state. Pure A at 1 mol L–1 is fed, and 90 % f A is converted in the CSTR. The space-time of the CSTR is _____________ seconds.
Q 4: Reactant A decomposes to products B and C in the presence of an enzyme in a well-stirred batch reactor. The kinetic rate expression is given by
-r_A=\frac{0.01C_A}{0.05+C_A}(mol\;L^{-1}\;min^{-1})If the initial concentration of A is 0.02 mol L–1, the time taken to achieve 50 % conversion of A is ______________ min (round off to 2 decimal places).
Q 5: The following homogeneous, irreversible reaction involving ideal gases,
A\rightarrow B+C;\;\;(-r_A)=0.5C_A(mol\;L^{-1}\;s^{-1})Is carried out in a steady state ideal plug flow reactor (PFR) operating at isothermal and isobaric conditions. The feed stream consists of pure A, entering at 2 m s-1. In order to achieve 50 % conversion of A, the required length of the PFR is _____________ meter (round off to 2 decimal places).