chemical engineering MCQs – Page 145

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 Review each marked answer and report any item that may be outdated or unclear.

chemical engineering Mcqs
2881. Inversion of cane sugar is an example of ______________________?
comments icon0

A. Bimolecular reaction with second order

B. Unimolecular reaction with first order

C. Bimolecular reaction with first order

D. Unimolecular reaction with second order

2882. The vessel dispersion number (D/?L) for plug flow is_________________?
comments icon0
A. 0

B. 500

C. 750

D. ?

2883. Which of the following is not a dimension-less group used in catalysis? (Where, D = dispersion co-efficient, cm2/sec.D1 = diffusion co-efficient; cm2/sec L = length of the reactor, cm t = time, sec, v = volumetric flow rate, cm3/sec. V = volume, cm3.) ?
comments icon0

A. Reduced time (vt/V)

B. Thiele modulus L ?(k/D1)

C. None of these

D. Reactor dispersion number (D/vL)

2884. In chamber process of sulphuric acid manufacture in industry, the gas phase oxidation of SO2 to SO3 is accomplished by a ______________ reaction ?
comments icon0

A. Non-catalytic homogeneous

B. Non-catalytic heterogeneous

C. Catalytic homogenous

D. Catalytic heterogeneous

2885. Space velocity____________________?
comments icon0
A. All A., B. and C.

B. Describes the extensive operating characteristics of a tubular flow reactor

C. Is the maximum feed rate per unit volume of reactor for a given conversion

D. Is a measure of the ease of the reaction

2886. Fractional conversion _________________ for an exothermic reversible chemical reaction, when the temperature is maximum?
comments icon0
A. Decreases

B. Remains unchanged

C. Unpredictable from the data

D. Increases

2887. Effectiveness factor of a catalyst pellet is a measure of the _________________ resistance?
comments icon0

A. Gas film

B. Chemical reaction

C. Pore diffusion

D. None of these

2888. Pure A in gas phase enters a reactor 50% of this A is converted to B through the reaction, A ? 3B. Mole fraction of A in the exit stream is______________________?
comments icon0

A. 5-Jan

B. 1/3

C. 4-Jan

D. 2-Jan

2889. A first order irreversible reaction, A ? B is carried out separately in a constant volume as well as in a variable volume reactor for a particular period. It signifies that _____________ in the two reactors?
comments icon0

A. Both conversion as well as concentration are same

B. Conversion in both will be the same but concentrations will be different

C. Both the conversion as well as concentrations will be different

D. None of these

2890. For identical flow rate, feed composition and for elementary first order reactions, N equal sized mixed reactors in series with a total volume V gives the same conversion as a single plug flow reactor of volume V for constant density systems. This is true, when the value of N is ___________________?
comments icon0

A. > 1

B. 1

C. ?

D. ? 1

2891. In an ideal P.F.R. at steady state conditions ___________________?
comments icon0

A. There may be diffusion along the flow path

B. The composition of reactants remains constant along a flow path

C. The conversion of the reactant varies from point to point along a flow path

D. There is no lateral mixing of fluid

2892. Kinetics of a solid catalysed reaction can best be studied in a _________________ reactor?
comments icon0

A. None of these

B. Plug-flow

C. Mixed

D. Batch

2893. The conversion for a second order, irreversible reaction (constant volume) as shown in the bellow figure, in batch mode is given by______________?
comments icon0

A. (k2 . CA0 . t)2/ (1 + k2 . CA0 . t)

B. 1/(1 + k2 . CA0 . t)

C. (k2 . CA0 . t)/ (1 + k2 . CA0 . t)2

D. (k2 . CA0 . t)/ (1 + k2 . CA0 . t)
2894. A chemical reaction occurs, when the energy of the reacting molecules is ________________ the activation energy of reaction?
comments icon0

A. Equal to

B. Less than

C. More than

D. Equal to or more than
2895. Rate of a chemical reaction is not affected by the____________________?
comments icon0
A. Number of molecules of reactants taking part in the reaction

B. Temperature

C. Catalyst

D. Reactants concentration

2896. For the gaseous reaction 2A ? B, where the feed consists of 50 mole % A and 50 mole % inerts, the expansion factor is___________________?
comments icon0

A. 1

B. -0.25

C. -0.5

D. 0

2897. Maximum equilibrium conversion for endothermic reaction is obtained at the ______________ temperature?
comments icon0

A. Lowest possible

B. Highest possible

C. Intermediate

D. Room

2898. Time required for 50% decomposition of a liquid in an isothermal batch reactor following first order kinetics is 2 minutes. The time required for 75% decomposition will be about _______________ minutes?
comments icon0
A. 4

B. 6

C. 10

D. 3

2899. Non-catalytic fluid-solid reactions are represented by _______________ model?
comments icon0

A. Continuous reaction

B. Unreacted core

C. Both A. and B.

D. Neither A. and B.

2900. A liquid decomposes by irreversible first order kinetics and the half life period of this reaction is 8 minutes. The time required for 75% conversion of the liquid will be ____________________ minutes?
comments icon0

A. 12

B. 16

C. 8

D. 4