Chemical Reaction Engineering MCQs Archives

231. The rate of the heterogenous catalytic reaction A(g) + B(g) ? C(g) is given by -rA = k.KA.pA.PB/(1 + KA.PA + Kc.pc), where KA and Kc are the adsorption equilibrium constants. The rate controlling step for this reaction isA. absorption of A.

Absorption of A

Surface reaction between absorbed A and absorbed B

Surface reaction between absorbed A and B in the gas phase

Surface reaction between A in the gas phase and absorbed B

✅ The correct answer is option C.

232. A plug-flow reactor is characterised by

High capacity

Presence of axial mixing

Presence of lateral mixing

Constant composition and temperature of reaction mixture

✅ The correct answer is option C.

233. A reaction which is catalysed by a base is catalysed by all substances which have a tendency to

Lose a proton

Gain a proton

Gain an electron

None of these

✅ The correct answer is option B.

234. Pick out the correct statement

Reactions with high activation energies are very temperature sensitive

Chemical equilibrium is a static state

A photochemical reaction is catalysed by light

A chemical reaction occurs when the energy of the reacting molecule is less than the activation energy of the reaction

✅ The correct answer is option A.

235. Kinetics of a solid catalysed reaction can best be studied in a __________ reactor.

Batch

Plug-flow

Mixed

None of these

✅ The correct answer is option C.

236. A catalyst loses its activity due to

Loss in surface area of the active component

Agglomeration of metal particles caused by thermal sintering of the solid surface

Covering of the catalytic active sites by a foregin substance

All of the above

✅ The correct answer is option D.

237. Which of the following is an autocatalytic reaction?

Photochemical reactions

Microbial fermentation reaction

Enzyme fermentation reaction

Ammonia synthesis reaction

✅ The correct answer is option B.

238. The heat of reaction

Depends on the pressure only

Depends on the mechanism of reaction only

Depends on both pressure and mechanism of reaction

Is independent of the mechanism of reaction

✅ The correct answer is option D.

239. __________ is the response curve for a step input signal from a reactor.

S-curve

C-curve

I-curve

None of these

✅ The correct answer is option B.

240. The rate of the reaction, X → Y, quadruples when the concentration of ‘X’ is doubled. The rate expression for the reaction is, r = K Cxn, the value of ‘n’ in this case will be

✅ The correct answer is option C.