Q 1: For a homogeneous reaction system, where Cj is the concentration of j at time t, Nj is the number of moles of j at time t, V is the reaction volume at time t, and t is the reaction time. The rate of reaction for species j is defined as
Q 2: The half-life of a first-order liquid phase reaction is 30 seconds. Then the rate constant, in min-1, is
Q 3: For a solid-catalyzed reaction, the Thiele modulus is proportional to
Q 4: The liquid-phase reaction A → B is conducted in an adiabatic plug flow reactor.
Data: Inlet concentration of A = 4.0 kmol/m3, Density of reaction mixture (independent of temperature) = 1200 kg/m3, Average heat capacity of feed stream (independent of temperature) = 2000 J/kg.K, and Heat of reaction (independent of temperature) = –120 kJ/mol of A reacting.
If the maximum allowable temperature in the reactor is 800 K, then the feed temperature (in K) should not exceed
Q 5: An isothermal pulse test is conducted on a reactor and the variation of the outlet tracer concentration with time is shown below:
The mean residence time of the fluid in the reactor (in minutes) is
Statement linked questions Q 6 & 7:
The liquid-phase reaction A → B + C is conducted isothermally at 50 °C in a continuous stirred tank reactor (CSTR). The inlet concentration of A is 8.0 gmol/liter. At a space-time of 5 minutes, the concentration of A at the exit of CSTR is 4.0 gmol/liter. The kinetics of the reaction is
-r_A=kC_A^{0.5}\frac{gmol}{liter.min}A plug flow reactor of the same volume is added in series after the existing CSTR.
Q 6: The rate constant (k) for this reaction at 50 °C is
Q 7: The concentration of A (in gmol/litre) at the exit of the plug flow reactor is