Chemical Reaction Engineering Exam Question

Department of Chemical Engineering Series Test 1- CH 010 502 Chemical Reaction Engineering Time: 1 hr

Maximum Marks:30

Part 1 1) At 500 k the rate of a bimolecular reaction is ten times the rate at 400 K. Find the activation energy of this reaction using Collision theory.(2 marks) 2) For an exothermic reversible reaction which one of the following correctly describes the dependence of equilibrium constant (K) with temperature (T) and pressure (P) ? a) K is independent of T and P b) K increases with increase in T and P c) K increases with T and decreases with P d) K decreases with an increase in T and is independent of P (1 marks) 3) For which reaction order, the half-life of the reactant is half of the full lifetime (time for 100% conversion) of the reactant? (A) Zero order (B) Half order (C) First order (D) Second order (1 marks) 4) For the chemical reaction P Q, it is found that the rate of reaction doubles as the concentration of 'P' is doubled. If the reaction rate is proportional to Cpn, then what is the value of 'n' for this chemical reaction ? (A) 1 (B) 2 (C) 3 (D) 0

(1 marks) Part 2 ( 3×5 = 15 marks) 1) The concentrations of a compound undergoing chemical change were 5.72, 3.23 and 1.96 at the times 0, 20 and 50 min from the commencement of reaction .Ascertain the order of the reaction. 2) Discuss various intermediates used in non-elementary chemical reactions 3) Briefly explain temperature dependence from Arrhenius theory Part 3 (10 marks) Answer any one of the following 1) The following data are obtained at 00C in a constant volume batch reactor using pure gaseous A: Time in min pA in mm Hg The reaction is A

0 760

2 60 0

4 475

6 390

8 320

10 275

12 240

2.5 K .Find the rate equation for this reaction. OR

2) a) Explain Psuedo-steady state hypothesis (PSSH)(3 marks)

14 215

∞ 150

Department of Chemical Engineering Series Test 1- CH 010 502 Chemical Reaction Engineering Time: 1 hr

Maximum Marks:30

b) Derive an integrated rate equation for an irreversible bi-molecular type second order reaction in terms of conversion. Also discuss its characteristics with respect to half life.(7 marks)