1. A liquid phase first order elementary reaction (A Products) occurs in a plug flow reactor that has a radius of 2 cm and a flow rate of 1.5 m³/min. If the conversion of reactant A is 96% and its specific rate constant of 9 s^-1, how long does the reactor need to be? If the initial concentration of A is doubled, how will that affect the length of the reactor? What parameter could be easily changed to reduce its required length by half?

2. a) The following reaction takes place in a CSTR :

A+B →2C

and has the following rate law :

r_c = K_cC_A²C_B

where kc = 0.04 L²/min mol²

Two inlet feeds, each of 15 L/min, are being combined before entering the CSTR yielding a total equimolar inlet feed of 90 mol/min. The two reactants have the same molar mass and density. If the reactor operates at steady state and the composition of C in the outlet stream is 1.2 mol/L, what is the size of the reactor?

Hint: C_A = C_B due to equimolar feed and stoichiometry

2. b) Due to an unexpected malfunction, both inlet and outlet streams are closed. C is a toxic chemical that is harmful if its concentration gets above 2.0 mol/L. How long do you have to get the products out before safety is a concern?