# Chemical Reaction Engineering GATE-1993

**Q 1:** The temperature dependence of chemical reaction rate in general can be written as,

What is the value of m from collision theory, transition state theory, and Arrhenius law?

**Q 2:** Every two minutes one reactor volume of feed is being treated at specified conditions in a continuous reactor. What is the space velocity?

**Q 3:** For multiple reactions,

2A\rightarrow R

2R\rightarrow S

The number of moles of S present when the number of moles of A and R is 0.3 and 0.5 respectively (initially 2 moles of A are only present) is,

**Q 4:** Sketch (rough diagram) exit age distribution, E(t) and cumulative age distribution function, F(t) for plug flow and perfectly mixed flow vessels and indicate the mean residence time and the maximum values of E(t) and F(t) in each case.

**Q 5:** The irreversible gas-phase reaction A β 3B will be carried out isothermally. The reaction is zero order, the initial concentration of A is 2 mol/lit and the system contains 40 % inert. The specific reaction gas constant is 0.10 mol/lit-min. Calculate the time required to achieve 80 % conversion in a constant-pressure batch reactor.

**Q 6:** At present a first-order, isothermal, liquid-phase reaction is being conducted in a cascade of two equal-sized mixed-flow reactors to obtain 95 % conversion. If a plug flow reactor of the same total volume replaces this system, what is the increase in the production rate for the same conversion?

**Q 7:** The observed rate using a cube of 2 cm catalyst pellet is 10-8 mol/s.cm3 pellet, calculate the value of the first-order reaction rate constant. The effective diffusivity is 0.01 cm^{2}/s.