MCQOPTIONS
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MCQOPTIONS
This section includes 409 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 301. |
For a first order chemical reaction, the rate constant_________________? |
| A. | Changes on changing the concentration units |
| B. | Is not a function of the unit of time |
| C. | Has unit of time-1 |
| D. | None of these |
| Answer» D. None of these | |
| 302. |
Following isothermal kinetic data are obtained in a basket type of mixed flow reactor for a porous catalyst. Determine the role of pore diffusion and external mass transfer processes ? |
| A. | Strong pore diffusion control and mass transfer not controlling |
| B. | Both pore diffusion and mass transfer not controlling |
| C. | Both pore diffusion and mass transfer controlling |
| D. | Mass transfer controlling |
| Answer» B. Both pore diffusion and mass transfer not controlling | |
| 303. |
Fluidised bed reactor is characterized by____________________? |
| A. | Uniformity of temperature |
| B. | Comparatively smaller equipment |
| C. | Very small pressure drop |
| D. | Absence of continuous catalyst regeneration facility |
| Answer» B. Comparatively smaller equipment | |
| 304. |
Fluid flow in a real packed bed can be approximated as ________________ model? |
| A. | Plug flow |
| B. | Dispersion |
| C. | Mixed flow |
| D. | Tank in series |
| Answer» C. Mixed flow | |
| 305. |
Find a mechanism that is consistent with the rate equation and reaction given below ?_x005F_x000D_2A + B → A2B, ( – rA) = k.CA.CB |
| A. | A + B ⇌ AB; AB + A → A2B |
| B. | A + B → AB; AB + A → A2B |
| C. | A + A → AA; AA + B → A2B |
| D. | A + A ⇌ AA; AA + B → A2B |
| Answer» E. | |
| 306. |
Exposure of a photographic plate to produce a latent image is an example of _______________ reaction? |
| A. | Very slow |
| B. | Very fast |
| C. | Photochemical |
| D. | Both B. and C. |
| Answer» E. | |
| 307. |
______________ explains the mechanism of catalysis? |
| A. | Activated complex theory |
| B. | Collision theory |
| C. | Thermodynamics |
| D. | None of these |
| Answer» B. Collision theory | |
| 308. |
Exothermic reactions are best carried out in ________________? |
| A. | A CSTR |
| B. | CSTR in series |
| C. | A plug flow reactor followed by CSTR |
| D. | CSTR followed by a plug flow reactor |
| Answer» E. | |
| 309. |
Equilibrium of a chemical reaction as viewed by kinetics is a ______________ state? |
| A. | Dynamic steady |
| B. | Static steady |
| C. | Dynamic unsteady |
| D. | None of these |
| Answer» B. Static steady | |
| 310. |
Enzymes are destroyed, when the_______________? |
| A. | Temperature is very high |
| B. | Reactant’s concentration is very high |
| C. | Reactant’s concentration is very low |
| D. | Reaction rate is independent of the reactant’s concentration |
| Answer» B. Reactant’s concentration is very high | |
| 311. |
Enzymes (a protein) are catalysts found in organisms. Its efficiency of catalysing a reaction is due to its capacity to lower the activation energy of the reaction. The enzyme ptyalin used for food digestion is present in ___________________? |
| A. | Blood |
| B. | Saliva |
| C. | Intestine |
| D. | Gland |
| Answer» C. Intestine | |
| 312. |
Effectiveness factor E. of a catalyst pellet is defined as, E = (actual rate within pore of the catalyst)/(rate if not snowed by pore diffusion), Effectiveness factor for a first order reaction is given by (where, T = Thiele modulus) ___________________? |
| A. | tan hT/T |
| B. | tan T/T |
| C. | tan hT/tan T |
| D. | None of these |
| Answer» B. tan T/T | |
| 313. |
Effectiveness factor of a catalyst pellet is a measure of the _________________ resistance? |
| A. | Pore diffusion |
| B. | Gas film |
| C. | Chemical reaction |
| D. | None of these |
| Answer» B. Gas film | |
| 314. |
Effective diffusivity (DE) in a catalyst pellet is related to molecular diffusivity (DN) and Knudsen diffusivity (DK) as_________________? |
| A. | DE = DM + DK |
| B. | 1/DE = 1/DN + DK |
| C. | DE = DM . DE |
| D. | DE = DN/DE |
| Answer» C. DE = DM . DE | |
| 315. |
During manufacture of H2SO4, the oxidation of SO2 to SO3 by oxygen is an endothermic reaction. The yield of SO3 will be maximised, if the _____________________? |
| A. | Temperature is increased |
| B. | Pressure is reduced |
| C. | Temperature is increased and pressure is reduced |
| D. | Temperature is reduced and pressure is increased |
| Answer» E. | |
| 316. |
Differential method for analysing the kinetic data is used ___________________? |
| A. | For testing complicated mechanisms |
| B. | When the data are scattered |
| C. | When rate expressions are very simple |
| D. | None of these |
| Answer» B. When the data are scattered | |
| 317. |
Design of heterogamous catalytic reactor involves consideration of _______________ steps? |
| A. | Only chemical |
| B. | Only physical |
| C. | Both A. & B. |
| D. | Neither A. nor B. |
| Answer» D. Neither A. nor B. | |
| 318. |
Decomposition rate of a liquid ‘X’ which decomposes as per the reaction as shown in the bellow figure is given by________________? |
| A. | K1 . CX |
| B. | (K1 + K2 + K3) CX |
| C. | (K1 + K2) CX |
| D. | (K2 + K3) CX |
| Answer» D. (K2 + K3) CX | |
| 319. |
Conversion increases with increase in temperature in case of a/an ______________ reaction? |
| A. | Autocatalytic |
| B. | Irreversible |
| C. | Reversible endothermic |
| D. | Reversible exothermic |
| Answer» D. Reversible exothermic | |
| 320. |
Considering the endothermic dissociation of CaCO3 in a closed vessel (CaCO3 ⇌ CaO + CO2), the pressure of CO2 increases, if____________________? |
| A. | A catalyst is added |
| B. | The temperature is increased |
| C. | An inert gas is pumped keeping the temperature constant |
| D. | None of these |
| Answer» C. An inert gas is pumped keeping the temperature constant | |
| 321. |
Consider the ‘n’ th order irreversible liquid phase reaction A → B. Which one of the following plots involving half life of the reaction (t1/2) and the initial reactant concentration (CA0) gives a straight line plot ? |
| A. | CA0 Vs t1/2 |
| B. | ln CA0 Vs t1/2 |
| C. | CA0 Vs ln t1/2 |
| D. | ln CA0 Vs ln t1/2 |
| Answer» D. ln CA0 Vs ln t1/2 | |
| 322. |
consecutive reaction, as shown in the bellow figure, is characterised by __________________? |
| A. | Maxima in the concentration of A |
| B. | Maxima in the concentration of B |
| C. | Maxima in the concentration of C |
| D. | High exothermicity |
| Answer» C. Maxima in the concentration of C | |
| 323. |
Concentration of the limiting reactant (with initial concentration of a moles/litre) after time t is (a-x). Then ‘t’ for a first order reaction is given by____________________? |
| A. | k. t = ln a/(a – x) |
| B. | k. t = x/a (a – x) |
| C. | k. t = ln (a – x)/a |
| D. | k. t = ln a (a – x)/x |
| Answer» B. k. t = x/a (a – x) | |
| 324. |
Collision theory gives the rate constant for bimolecular reaction as___________________? |
| A. | K α √T.e-E/RT |
| B. | K α eE/RT |
| C. | K α e-E/RT |
| D. | None of these |
| Answer» D. None of these | |
| 325. |
Cold shot cooling is only practical when the feed temperature is ______________ than the reaction temperature? |
| A. | Higher |
| B. | Much higher |
| C. | Lower |
| D. | Much lower |
| Answer» E. | |
| 326. |
Chemical reaction rate of a component depends upon the______________________? |
| A. | Composition of the component only |
| B. | Temperature of the system |
| C. | Pressure of the system |
| D. | All A., B. and C. |
| Answer» E. | |
| 327. |
Chemical kinetics can predict the _______________ of a chemical reaction? |
| A. | Rate |
| B. | Feasibility |
| C. | Both A. & B. |
| D. | Neither A. nor B. |
| Answer» B. Feasibility | |
| 328. |
______________ catalytic reaction is involved in the thermal cracking of gas oil ? |
| A. | Homogeneous |
| B. | Non-Homogeneous |
| C. | Heterogeneous |
| D. | Non-Heterogeneous |
| Answer» B. Non-Homogeneous | |
| 329. |
Catalytic action in a catalytic chemical reaction follows from the ability of catalyst to change the ___________________? |
| A. | Activation energy |
| B. | Equilibrium constant |
| C. | Heat of reaction |
| D. | None of these |
| Answer» B. Equilibrium constant | |
| 330. |
Catalyst is a substance, which ________________ chemical reaction? |
| A. | Increases the speed of a |
| B. | Decreases the speed of a |
| C. | Can either increase or decrease the speed of a |
| D. | Alters the value of equilibrium constant in a reversible |
| Answer» D. Alters the value of equilibrium constant in a reversible | |
| 331. |
Catalyst carriers___________________? |
| A. | Have very high selectivity |
| B. | Increase the activity of a catalyst |
| C. | Provide large surface area with a small amount of active material |
| D. | Inhibit catalyst poisoning |
| Answer» D. Inhibit catalyst poisoning | |
| 332. |
Carbon particles accumulated on the catalyst used in the gas oil cracking lies in the category of _____________________ poison? |
| A. | Deposited |
| B. | Chemisorbed |
| C. | Selectivity |
| D. | Stability |
| Answer» B. Chemisorbed | |
| 333. |
Calcination reaction of limestone (CaCO3 → CaO + CO2) goes to completion in the rotary kiln, because____________________? |
| A. | CaO is not dissociated |
| B. | CO2 escapes continuously |
| C. | Of high calcination temperature |
| D. | CaO is more stable than CaCO3 |
| Answer» C. Of high calcination temperature | |
| 334. |
Bulk diffusion in catalyst pore _______________ with increase in pressure? |
| A. | Increases |
| B. | Decreases |
| C. | Remains unchanged |
| D. | Increases exponentially |
| Answer» C. Remains unchanged | |
| 335. |
Brunauer, Emmet and Teller (BET) equation is used to determine the specific surface area of a porous particle but not the pore volume & the porosity of the catalyst bed. Which of the following postulates is not used to derive BET equation ? |
| A. | Langmuir’s assumption applies to every adsorbed layer |
| B. | There is no dynamic equilibrium between successive layer |
| C. | The adsorbed layer may be polymolecular in thickness and the heat of adsorption in each layer (except the first one) is involved in each of the evapor |
| D. | None of these |
| Answer» C. The adsorbed layer may be polymolecular in thickness and the heat of adsorption in each layer (except the first one) is involved in each of the evapor | |
| 336. |
B.E.T. method of finding out surface area of a catalyst, uses the extension of _________________ isotherm? |
| A. | Langmuir |
| B. | Freundlich |
| C. | Tempkin |
| D. | None of these |
| Answer» B. Freundlich | |
| 337. |
BET apparatus_______________________? |
| A. | Measures the catalyst surface area directly |
| B. | Operates at very high pressure |
| C. | Is made entirely of stainless steel |
| D. | None of these |
| Answer» E. | |
| 338. |
B.E.T. method can be used to determine the ___________________ of a porous catalyst? |
| A. | Solid density |
| B. | Pore volume |
| C. | Surface area |
| D. | All A., B. and C. |
| Answer» D. All A., B. and C. | |
| 339. |
BET apparatus is used to determine the ___________________? |
| A. | Specific surface of a porous catalyst |
| B. | Pore size distribution |
| C. | Pore diameter |
| D. | Porosity of the catalyst bed |
| Answer» B. Pore size distribution | |
| 340. |
Backmixing is most predominant in___________________? |
| A. | A well stirred batch reactor |
| B. | A plug-flow reactor |
| C. | A single CSTR |
| D. | CSTR’s connected in series |
| Answer» D. CSTR’s connected in series | |
| 341. |
Autocatalytic reactions are best carried out in a_________________? |
| A. | CSTR |
| B. | CSTR in series |
| C. | Plug flow reactor |
| D. | Recycle reactor |
| Answer» E. | |
| 342. |
At a given value of E/R (ratio of activation energy and gas constant), the ratio of the rate constants at 500°K and 400°K is 2, if Arrhenius law is used. What will be this ratio, if transition state theory is used with the same value of „E/R‟ ? |
| A. | 1.6 |
| B. | 2 |
| C. | 2.24 |
| D. | 2.5 |
| Answer» E. | |
| 343. |
At a given temperature, K1, K2 and K3 are equilibrium constants for the following reactions 1, 2, 3 respectively. CH4(g) + H2O(g) ⇌ CO(g) + 3H2(g), CO(g) + H2O(g) ⇌ CO2(g) + H2(g) CH4(g) + 2H2O(g) ⇌ CO2(g) + 4H2(g) Then K1, K2 and K3 are related as ? |
| A. | K3 = K1.K2 |
| B. | K3 = (K1.K2)0.5 |
| C. | K3(K1+K2)/2 |
| D. | K3 = (K1.K2)2 |
| Answer» B. K3 = (K1.K2)0.5 | |
| 344. |
As the chemical reaction proceeds, the rate of reaction ___________________? |
| A. | Increases |
| B. | Decreases |
| C. | Remain same |
| D. | May increase or decrease depending on the type of reaction |
| Answer» C. Remain same | |
| 345. |
Arrhenius equation shows the variation of ___________________ with temperature? |
| A. | Reaction rate |
| B. | Rate constant |
| C. | Energy of activation |
| D. | Frequency factor |
| Answer» C. Energy of activation | |
| 346. |
Arrhenius equation represents graphically the variation between the ______________ and temperature? |
| A. | Rate of reaction |
| B. | Frequency factor |
| C. | Rate constant |
| D. | Activation energy |
| Answer» D. Activation energy | |
| 347. |
An isothermal irreversible reaction is being carried out in an ideal tubular flow reactor. The conversion in this case will ______________ with decrease in space time? |
| A. | Increase |
| B. | Increase exponentially |
| C. | Decrease |
| D. | Remain unchanged |
| Answer» D. Remain unchanged | |
| 348. |
An isothermal aqueous phase reversible reaction, P ⇌ R, is to be carried out in a mixed flow reactor. The reaction rate in k.mole/m3 .h is given by, r = 0.5CP – 0.125CR. A stream containing only P enters the reactor. The residence time required (in hours) for 40% conversion of P is_________________? |
| A. | 0.80 |
| B. | 1.33 |
| C. | 1.60 |
| D. | 2.67 |
| Answer» D. 2.67 | |
| 349. |
An irreversible first order reaction is being carried out in a CSTR and PFR of same volume. The liquid flow rates are same. The relative conversion will__________________? |
| A. | Be more in CSTR than in PFR |
| B. | Be more in PFR than in CSTR |
| C. | Be same in both cases |
| D. | Depend on the temperature |
| Answer» C. Be same in both cases | |
| 350. |
An irreversible aqueous phase reaction, A + B → P, is carried out in an adiabatic mixed flow reactor. A feed containing 4kmole/m3 of each A and B enters the reactor at 8m3 /hr. If the temperature of the exit stream is never to exceed 390 K, what is the maximum inlet feed temperature allowed? Data: Heat of reaction = – 50 kJ/mole Density of the reacting mixture = 1000kg/m3 Specific heat of reacting mixture = 2kJ/kg.K The above data can be assumed to be independent of temperature and composition? |
| A. | 190 |
| B. | 290 |
| C. | 390 |
| D. | 490 |
| Answer» C. 390 | |