Explore topic-wise MCQs in Chemical Engineering.

This section includes 119 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.

101.

The effect of increasing pressure on the gaseous equilibrium of the reaction 2 X +3 Y 3 X +2 Y 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.
102.

For reactions in parallel viz A P (desired product) and A Q (unwanted product), if the order of the desired reaction is higher than that of the undesired reaction, a

A. batch reactor is preferred over a single CSTR for high yield.
B. tubular reactor is preferred over a single CSTR for high yield.
C. both (a) and (b).
D. single CSTR is the most suitable.
Answer» D. single CSTR is the most suitable.
103.

For a gaseous phase reaction, rate of reaction is equal to K . C A . C B . If the volume of the reactor is suddenly reduced to l/4th of its initial volume, then the rate of reaction compared to the original rate will be __________ times.

A. 8
B. 16
C. 1/8
D. 1/16
Answer» C. 1/8
104.

What is the Thiele modulus of the solid catalysed first order reaction, , if the pore diffusion offers negligible resistance to reaction ?

A. < 5
B. < 0.5
C. > 1
D. 5
Answer» C. > 1
105.

At a given temperature, K 1 , K 2 and K 3 are equilibrium constants for the following reactions 1, 2, 3 respectively. CH 4 (g) + H 2 O(g) CO(g) + 3H 2 (g), CO(g) + H 2 O(g) CO 2 (g) + H 2 (g) CH 4 (g) + 2H 2 O(g) CO 2 (g) + 4H 2 (g) Then K 1 , K 2 and K 3 are related as:

A. K 3 = K 1 . K 2
B. K 3 = ( K 1 . K 2 ) 0.5
C. K 3 ( K 1 + K 2 )/2
D. K 3 = ( K 1 . K 2 ) 2
Answer» B. K 3 = ( K 1 . K 2 ) 0.5
106.

Unreacted core model' represents the reaction involving

A. combustion of coal particles.
B. roasting of sulphide ores.
C. manufacture of carbon disulphide from elements.
D. none of these.
Answer» C. manufacture of carbon disulphide from elements.
107.

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 Arrhenious 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.
108.

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.

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.
Answer» C. both the conversion as well as concentrations will be different
109.

Fractional conversion __________ with increase in pressure for ammonia synthesis reaction i.e ., N 2 + 3H 2 2NH 3 .

A. increases
B. decreases
C. remains unchanged
D. unpredictable from the data
Answer» B. decreases
110.

The dimensions of rate constant for reaction 3 A B are (l/gm mole)/min. Therefore the reaction order is

A. 0
B. 1
C. 2
D. 3
Answer» D. 3
111.

For the irreversible elementary reactions in parallel viz , the rate of disappearance of ' X ' is equal to

A. C A ( K 1 + K 2 )
B. C A ( K 1 + K 2 )/2
C. C A . K 1 /2
D. C A . K 2 /2
Answer» B. C A ( K 1 + K 2 )/2
112.

N ' plug flow reactors in series with a total volume ' V ' gives the same conversion as a single plug flow reactor of volume ' V ' for __________ order reactions.

A. first
B. second
C. third
D. any
Answer» E.
113.

The rate constant of a chemical reaction increases by 100 times when the temperature is increased from 400 °K to 500 °K. Assuming transition state theory is valid, the value of E/R is

A. 8987°K
B. 9210°K
C. 8764°K
D. 8621°K
Answer» C. 8764°K
114.

In a consecutive reaction system when E 1 is much greater than E 2 , the yield of B increases with the

A. increase of temperature.
B. decrease of temperature.
C. increase in initial concentration of A .
D. decrease in initial concentration of A .
Answer» B. decrease of temperature.
115.

For a reaction of the type, , the rate of reaction (- r x ) is given by

A. ( K 1 + K 1 ) C X
B. ( K 1 + K 2 + K 3 ) C X
C. K 1 C V - K 2 C X
D. ( K 1 - K 2 ) C X
Answer» D. ( K 1 - K 2 ) C X
116.

6 gm of carbon is burnt with an amount of air containing 18 gm oxygen. The product contains 16.5 gms CO 2 and 2.8 gms CO besides other constituents. What is the degree of conversion on the basis of disappearance of limiting reactant ?

A. 100%
B. 95%
C. 75%
D. 20%
Answer» C. 75%
117.

For every 10°C rise in temperature, the rate of chemical reaction doubles. When the temperature is increased from 30 to 70°C, the rate of reaction increases __________ times.

A. 8
B. 12
C. 16
D. 32
Answer» D. 32
118.

What is the order of a chemical reaction, , if the rate of formation of ' C ', increases by a factor of 2.82 on doubling the concentration of ' A ' and increases by a factor of 9 on trebling the concentration of ' B '?

A. 7/2
B. 7/4
C. 5/2
D. 5/4
Answer» B. 7/4
119.

The fractional volume change of the system for the isothermal gas phase reaction, A 3 B , between no conversion and complete conversion is

A. 0.5
B. 1
C. 2
D. 3
Answer» D. 3