chemical engineering chemical reaction MCQs – Page 9

Practise multiple-choice questions from chemical engineering chemical reaction for competitive examinations and subject revision. Review each marked answer and report any item that may be outdated or unclear.

chemical engineering chemical reaction Mcqs

161. For the gaseous reaction 2A ? B, where the feed consists of 50 mole % A and 50 mole % inerts, the expansion factor is___________________?
0

A. -0.25

B. -0.5

C. 1

D. 0

162. A catalyst in a chemical reaction____________________?
0

A. All A., B. and C.

B. Decreases the activation energy

C. Alters the reaction mechanism

D. Increases the frequency of collisions of reacting species

163. The optimum performance for reactors operating in parallel is obtained when the feed stream is distributed in such a way, that the_________________?
0

A. Larger reactors have more space time compared to smaller ones

B. None of these

C. Space time for each parallel line is same

D. Space time for parallel lines is different

164. Mean residence time is equal to the space time, when_________________?
0

A. The temperature, pressure and the density of reaction mixture remains constant throughout the

B. The feed rate is measured at temperature and pressure in the reactor

C. ctor

D. All A., B. and C.

E. There is no change in number of moles in gaseous reaction

165. Which of the following is not a unit of reaction rate ?
0

A. Moles formed/volume of reactor) (time)

B. Moles for med/(surface of catalyst) (time)

C. None of these

D. Mole formed/volume of catalyst) (time)

166. Collision theory gives the rate constant for bimolecular reaction as___________________?
0

A. None of these

B. K ? ?T.e-E/RT

C. K ? eE/RT

D. K ? e-E/RT

167. Which of the following fixes the volume of a batch reactor for a particular conversion and production rate ?
0

A. Operating conditions (e.g. pressure and temperature)

B. Density of mixture

C. None of these

D. Rate constant

168. A plug-flow reactor is characterized by _____________________?
0

A. Presence of axial mixing

B. Presence of lateral mixing

C. High capacity

D. Constant composition and temperature of reaction mixture

169. Which of the following is not a theory of homogeneous reaction ?
0

A. Collision theory and activated complex theory

B. Chain reaction theory

C. Radiation hypothesis

D. None of these

170. Decomposition rate of a liquid X which decomposes as per the reaction as shown in the bellow figure is given by________________?
0

A. (K1 + K2 + K3) CX

B. (K1 + K2) CX

C. K1 . CX

D. (K2 + K3) CX

171. A first order reaction A ? B occurs in an isothermal porous catalyst pellet of spherical shape. If the concentration of A at the centre of the pellet is much less than at the external surface, the process is limited by__________________?
0

A. External mass transfer

B. Diffusion within the pellet

C. Reaction

D. None of the above

172. The enzyme which can catalyse the conversion of glucose to ethyl alcohol is ___________________?
0

A. Maltase

B. Diastase

C. Invertase

D. Zymase

173. A batch reactor suffers from following disadvantage ?
0

A. All A., B. and C.

B. Poor product quality control

C. High labour and handling cost

D. High shutdown time requirement for emptying, cleaning and refilling

174. The rate expression for a heterogeneous catalytic reaction is given by, rA = K.KA PA(1 + KA.PA + KR.PR), where K is surface reaction rate constant and KA and KR are absorption equilibrium constants of A and R respectively. If KR PR >> (1 + KA PA), the apparent activation energy EA is equal to (given E is the activation energy for the reaction and ?HR and ?HA are the activation energies of adsorption of R and A) ?
0

A. E + ?HA

B. E

C. ?HA + ?HR

D. E + ?HA ?HR)

175. Most important characteristics of gas-liquid reactors are the________________?
0

A. Specific inter-facial area

B. Liquid hold-up

C. Both A. and B.

D. None of these

176. The order of the chemical reaction as shown in the bellow figure, whose rate equation is given as -rA = KCA_________________?
0

A. 0

B. 2

C. 1

D. 3

E. CB is

177. Kinetics of a catalytic reaction can be best studied on a/an ______________ reactor?
0

A. Integral (plug flow)

B. Mixed

C. Differential (flow)

D. Either A., B. and C.

178. In an exothermic reaction, the energy of the reacting substances as compared to that of products is____________________?
0

A. Either A. or B., depends on order of reaction

B. More

C. Less

D. Same

179. The minimum energy required to allow a chemical reaction to proceed is termed as the threshold energy . Chemical reactions with low activation energy are ________________?
0

A. Insensitive to temperature changes

B. Highly temperature sensitive

C. Always irreversible

D. Mostly irreversible

180. If pore diffusion is the controlling step in a solid catalysed reaction, the catalyst___________________?
0

A. Porosity is of less importance

B. Internal surface area is utilised efficiently

C. None of these

D. Porosity is very important

Previous Next

Showing 161 to 180 of 472 mcqs