MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 1443 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 501. |
%_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 | |
| 502. |
%_Arhenious 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 | |
| 503. |
%_In case of staged packed bed reactors carrying out exothermic reaction, use_% |
| A. | High recycle for pure gas |
| B. | Plug flow for dilute liquid requiring no large preheating of feed |
| C. | Cold shot operations for a dilute solution requiring large preheating to bring the stream upto the reaction temperature |
| D. | All of the above |
| Answer» E. | |
| 504. |
%_In which of the following gaseous phase reactions, the equilibrium of the reaction remains unaffacted by pressure changes ?_% |
| A. | 2O? ? 3O? |
| B. | N? + O? ? 2NO |
| C. | 2NO? ? N?O? |
| D. | 2SO? + O? ? 2SO? |
| Answer» C. 2NO? ? N?O? | |
| 505. |
%_The dimensions of rate constant for reaction 3A ‚Üí B are (l/gm mole)/min. Therefore the reaction order is_% |
| A. | 0 |
| B. | 1 |
| C. | 2 |
| D. | 3 |
| Answer» D. 3 | |
| 506. |
%_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. | |
| 507. |
%_A chemical reaction is of zero order, when the reaction rate is (where, CA = concentration of reactant)_% |
| A. | ‚Äö√ √π CA |
| B. | ‚Äö√ √π 1/CA |
| C. | Independent of temperature |
| D. | None of these |
| Answer» E. | |
| 508. |
%_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 | |
| 509. |
%_The effect of increasing pressure on the gaseous equilibrium of the reaction 2X+3Y ‚Äö√°√£ 3X+2Y indicates that_% |
| A. | Pressure has no effect |
| B. | Backward reaction is favoured |
| C. | Forward reaction is favoured |
| D. | None of these |
| Answer» B. Backward reaction is favoured | |
| 510. |
%_Which of the following does not produce a change in the value of rate constant of a reaction?_% |
| A. | Pressure |
| B. | Temperature |
| C. | Concentration and catalyst |
| D. | None of these |
| Answer» D. None of these | |
| 511. |
%_A catalyst inhibitor_% |
| A. | Lessens its selectivity |
| B. | May be useful for suppressing undesirable side reactions |
| C. | Is added in small quantity during the catalyst manufacture itself |
| D. | All of the above |
| Answer» E. | |
| 512. |
%_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. | |
| 513. |
%_For a first order chemical reaction in a porous catalyst, the Thiele modulus is 10. The effectiveness factor is approximately equal to_% |
| A. | 1 |
| B. | 0.5 |
| C. | 0.1 |
| D. | 0 |
| Answer» D. 0 | |
| 514. |
_ The conversion XA and residence time data are collected for zero order liquid phase reaction in a stirred tank reactor. Which of the following will be a straight line?$? |
| A. | XA Vs . τ |
| B. | XA Vs ln τ |
| C. | XA/(1 - XA)Vs τ |
| D. | XA(1 - XA)Vs τ |
| Answer» B. XA Vs ln ≈ì√ë | |
| 515. |
_ Differential method for analysing the kinetic data is used$? |
| 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 | |
| 516. |
_ Rate of a chemical reaction is independent of the concentration of the reactants for a __________ reaction.$? |
| A. | Zero order |
| B. | Third order |
| C. | Consecutive |
| D. | None of these |
| Answer» B. Third order | |
| 517. |
_ Sometimes, batch process is preferred over continuous process, when the product$? |
| A. | Quality & yield can not be achieved in continuous processes, because of long residence time |
| B. | Sales demand is fluctuating |
| C. | Both A & B |
| D. | Neither A nor B |
| Answer» D. Neither A nor B | |
| 518. |
_ Molecularity of a reaction$? |
| A. | Is always equal to the overall order of reaction |
| B. | May not be equal to the order of reaction |
| C. | Can |
| D. | Both B and C |
| Answer» E. | |
| 519. |
_ __________ resistance is not involved in the combustion of a carbon particle.$? |
| A. | Gas film |
| B. | Ash |
| C. | Chemical reaction |
| D. | None of these |
| Answer» C. Chemical reaction | |
| 520. |
_ For a first order reaction carried out in a plug flow reactor, the space time is$? |
| A. | 1/K In C0/C |
| B. | 1/K In C/C0 |
| C. | K In C0/C |
| D. | K In C/C0 |
| Answer» B. 1/K In C/C0 | |
| 521. |
_ The decomposition of A into B is represented by the exothermic reaction, A ‚Äö√°√£ 2B. To achieve maximum decomposition, it is desirable to carry out the reaction.$? |
| A. | At high P and high T |
| B. | At low P and high T |
| C. | At low P and low T |
| D. | At high P and low T |
| Answer» D. At high P and low T | |
| 522. |
_ Ionic reactions occur in$? |
| A. | Solid state only |
| B. | Liquid state only |
| C. | Solutions |
| D. | Any state |
| Answer» D. Any state | |
| 523. |
_ For the non catalytic reaction of particles with surrounding fluid, the same needed to achive the same fractional conversion for particles of different unchanging sizes is proportional to the particle diameter, when the __________ is the controlling resistance.$? |
| A. | Film diffusion |
| B. | Diffusion through ash layer |
| C. | Chemical reaction |
| D. | Either A, B or C |
| Answer» D. Either A, B or C | |
| 524. |
_ In case of a P.F.R., there$? |
| A. | May be lateral mixing of fluid |
| B. | Should not be any mixing along the flow path |
| C. | Both A and B |
| D. | Neither A nor B |
| Answer» D. Neither A nor B | |
| 525. |
_ For a packed bed reactor; the presence of a long tail in the residence time distribution curve is an indication of$? |
| A. | Ideal plug flow |
| B. | Bypass |
| C. | Dead zone |
| D. | Chanelling |
| Answer» D. Chanelling | |
| 526. |
_ For the chemical reaction X ‚Üí Y, it is observed that, on doubling the concentration of 'X', the reaction rate quadruples. If the reaction rate is proportional to Cxn, then what is the value of 'n' ?$? |
| A. | 4 |
| B. | 1/4 |
| C. | 16 |
| D. | 2 |
| Answer» B. 1/4 | |
| 527. |
_ The value of steric factor 'P' in the equation k = PZeE/RT usually ranges from$? |
| A. | L.0 to 10⁻⁸ |
| B. | L.l.to 10² |
| C. | 0.1 to 0.9 |
| D. | None of these |
| Answer» B. L.l.to 10¬¨‚⧠| |
| 528. |
_ The size of plug flow reactor (PFR) for all positive reaction orders and for any given duty, is __________ that of mixed reactor.$? |
| A. | Greater than |
| B. | Equal to |
| C. | Smaller than |
| D. | Unpredictable from the data |
| Answer» D. Unpredictable from the data | |
| 529. |
_ For reaction, P + 2 ‚Üí 3R, molar rate of consumption of P is$? |
| A. | Double of that of Q |
| B. | Same as that of Q |
| C. | Half of that of Q |
| D. | 2/3rd of that of Q |
| Answer» D. 2/3rd of that of Q | |
| 530. |
_ A catalyst in a chemical reaction$? |
| A. | Decreases the activation energy |
| B. | Alters the reaction mechanism |
| C. | Increases the frequency of collisions of reacting species |
| D. | All of the above |
| Answer» E. | |
| 531. |
_ The use of space time is preferred over the mean residence time in the design of a/an$? |
| A. | Batch reactor |
| B. | Ideal tubular-flow reactor |
| C. | Slurry reactor |
| D. | CSTR |
| Answer» C. Slurry reactor | |
| 532. |
_ BET apparatus$? |
| A. | Measures the catalyst surface area directly |
| B. | Operates at very high pressure |
| C. | Is made entirely of stainless steel |
| D. | None of these |
| Answer» E. | |
| 533. |
_ Effectiveness factor (E) of a catalyst pellet is defined as, E = (actual rate within pore of catalyst/rate if notsnowed by pore diffusion) Effectiveness factor for a first order reaction is given by (where, T = Thiele modulus)$? |
| A. | Tan hT/T |
| B. | Tan T/T |
| C. | Tan hT/tan T |
| D. | None of these |
| Answer» B. Tan T/T | |
| 534. |
_ For a tubular flow reactor with uniform concentration and temperature, the independent variable is$? |
| A. | Time |
| B. | Length |
| C. | Diameter |
| D. | None of these |
| Answer» C. Diameter | |
| 535. |
_ A first order reaction A ‚Üí B occurs in an isothermal porous catalyst pellet of spherical shape. If the concentration of A at the centre of the pellet is much less than at the external surface, the process is limited by$? |
| A. | Diffusion within the pellet |
| B. | Reaction |
| C. | External mass transfer |
| D. | None of the above |
| Answer» B. Reaction | |
| 536. |
_ For a first order chemical reaction, the rate constant$? |
| A. | Changes on changing the concentration units |
| B. | Is not a function of the unit of time |
| C. | Has unit of time⁻¹ |
| D. | None ofthese |
| Answer» D. None ofthese | |
| 537. |
_ In a reaction, the threshold energy is equal to (where, A = activation energy N = normal energy of reactants)$? |
| A. | A |
| B. | N |
| C. | A+N |
| D. | A-N |
| Answer» D. A-N | |
| 538. |
_ A catalyst promoter$? |
| A. | Improves the activity of a catalyst |
| B. | Acts as a catalyst support |
| C. | Itself has very high activity |
| D. | All of the above |
| Answer» B. Acts as a catalyst support | |
| 539. |
_ An autothermal reactor is$? |
| A. | Most suitable for a second order reaction |
| B. | Most suitable for a reversible reaction |
| C. | Completely self-supporting in its thermal energy requirements |
| D. | Isothermal in nature |
| Answer» D. Isothermal in nature | |
| 540. |
_ Kinetics of a catalytic reaction can be best studied on a/an __________ reactor.$? |
| A. | Mixed |
| B. | Integral (plug flow) |
| C. | Differential (flow) |
| D. | Either A, B and C |
| Answer» E. | |
| 541. |
_ Rate of a chemical reaction is not affected by the$? |
| A. | Catalyst |
| B. | Temperature |
| C. | Reactant's concentration |
| D. | Number of molecules of reactants taking part in the reaction |
| Answer» E. | |
| 542. |
_ A gaseous reactant is introduced in a mixed reactor of 3 litres volume at the rate of 1 litre/second. The space time is __________ seconds.$? |
| A. | 1 |
| B. | 3 |
| C. | 1/3 |
| D. | 32 |
| Answer» C. 1/3 | |
| 543. |
_ The reaction A → B is conducted in an adiabatic plug flow reactor (PFR). Pure A at a concentration of 2 kmol/m³ is fed to the reactor at the rate of 0.01 m³ /s and at a temperature of 500 K. If the exit conversion is 20%, then the exit temperature (in k)is (Data: Heat of reaction at 298 K = - 50000 kJ/ kmole of A reacted Heat capacities CPA = CPB = 100kJ/kmole. K (may be assumed to be independent of temperature))$? |
| A. | 400 |
| B. | 500 |
| C. | 600 |
| D. | 1000 |
| Answer» D. 1000 | |
| 544. |
_ Sulphuric acid is used as a catalyst in the$? |
| A. | Hydrogenation of oils |
| B. | Gas phase oxidation of SO‚ÇÇ in chamber process |
| C. | Alkylation of hydrocarbons |
| D. | None of these |
| Answer» D. None of these | |
| 545. |
_ An imbalanced chemical reaction equation is against the law of$? |
| A. | Multiple proportion |
| B. | Conservation of mass |
| C. | Constant proportion |
| D. | None of these |
| Answer» C. Constant proportion | |
| 546. |
_ Velocity of a chemical reaction$? |
| A. | Decreases with increase in temperature |
| B. | Increases with increase of pressure of reactants for all reactions |
| C. | Decreases with increase of reactant concentration |
| D. | None of these |
| Answer» E. | |
| 547. |
_ For a first order isothermal chemical reaction in a porous catalyst, the effectiveness factor is 0.3. The effectiveness factor will increase if the$? |
| A. | Catalyst size is reduced or the catalyst diffusivity is reduced |
| B. | Catalyst size is reduced or the catalyst diffusivity is increased |
| C. | Catalyst size is increased or the catalyst diffusivity is reduced |
| D. | Catalyst size is increased or the catalyst diffusivity is increased |
| Answer» C. Catalyst size is increased or the catalyst diffusivity is reduced | |
| 548. |
_ Half life period of a chemical reaction is$? |
| A. | The time required to reduce the concentration of the reacting substance to half its initial value |
| B. | Half of the space time of a reaction |
| C. | Half of the residence time of a reaction |
| D. | None of these |
| Answer» B. Half of the space time of a reaction | |
| 549. |
_ An endothermic aqueous phase first order irreversible reaction is carried out in an adiabatic plug flow reactor. The rate of reaction$? |
| A. | Is maximum at the inlet of the reactor |
| B. | Goes through a maximum along the length of the reactor |
| C. | Goes through a minimum along the length of the reactor |
| D. | Is maximum at the exit of the reactor |
| Answer» B. Goes through a maximum along the length of the reactor | |
| 550. |
_ 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.$? |
| A. | Absorption of A |
| B. | Surface reaction between absorbed A and absorbed B |
| C. | Surface reaction between absorbed A and B in the gas phase |
| D. | Surface reaction between A in the gas phase and absorbed B |
| Answer» D. Surface reaction between A in the gas phase and absorbed B | |