Chemical Reaction Engineering MCQs

Question 1

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

Accepted Answer

1.6

Answer

0.8

Answer

1.33

Answer

2.67

Question 2

The time needed to achieve the same fractional conversion for particles of different sizes (d) when chemical reaction controls, is proportional to

Accepted Answer

d

Answer

$$\sqrt {	ext{d}} $$

Answer

d1.5

Answer

d2

Question 3

According to the 'law of mass action', the rate of reaction is directly proportional to the

Accepted Answer

Molar concentration of the reactants

Answer

Equilibrium constant

Answer

Volume of the reaction vessel

Answer

Nature of the reactants

Question 4

What is the dispersion number for a CSTR?

Accepted Answer

∞

Answer

0

Answer

1

Answer

< 1

Question 5

For an ideal mixed flow reactor (CSTR), the exit age distribution E(t) is given by

Accepted Answer

None of the above

Answer

A dirac delta function

Answer

A step function

Answer

A ramp function

Question 6

Mean residence time is equal to the space time, when

Accepted Answer

All of the above

Answer

The feed rate is measured at temperature and pressure in the reactor

Answer

The temperature, pressure and the density of reaction mixture remains constant throughout the reactor

Answer

There is no change in number of moles in gaseous reaction

Question 7

A space time of 3 hours for a flow reactor means that

Accepted Answer

The time required to process one reactor volume of feed (measured at specified conditions) is 3 hours

Answer

Three reactor volumes of feed can be processed every hour

Answer

It takes three hours to dump the entire volume of the reactor with feed

Answer

Conversion is cent per cent after three hours

Question 8

Which of the following will give maximum gas conversion?

Accepted Answer

Semi-fluidised bed reactor

Answer

Fixed bed reactor

Answer

Fluidised bed reactor

Answer

Plug-flow catalytic reactor

Question 9

For the same residence time, which one will give the maximum conversion?

Accepted Answer

Single tubular flow reactor (v = 5 litres)

Answer

Single stirred tank (v = 5 litres)

Answer

Two stirred tank (each of 2.5 litres) in series

Answer

Stirred tank followed by tubular flow reactor (each of 2.5 litres)