Chemical Reaction Engineering MCQs

Question 1

Shift conversion reaction

Accepted Answer

Converts CO to CO2 with steam

Answer

Converts N2 and H2 into NH3

Answer

Is non-catalytic

Answer

Is highly exothermic

Question 2

The following gas phase reactions are carried out isothermally in a CSTR. A → 2R; r1 = k1pA; k1 = 20 mole/(sec.m3.bar) A → 3S; r2 = k2pA; k2 = 40 mole/(sec.m3.bar) What is the maximum possible value of FR (mole/sec)?

Accepted Answer

$$\frac{2}{3}$$

Answer

$$\frac{1}{3}$$

Answer

$$\frac{1}{2}$$

Answer

2

Question 3

When the density of the reaction mixture is constant in a chemical reaction, the ratio of the mean residence time to space time is

Accepted Answer

1

Answer

> 1

Answer

< 1

Answer

0

Question 4

Pick out the wrong statement.

Accepted Answer

A catalyst increases the potential energy barrier over which the reactants must pass to form products

Answer

Exit age description function (E) and internal age distribution function ($$I$$) are related as, $$E = - \frac{{{	ext{d}}I}}{{{	ext{d}}	heta }}$$

Answer

Chmisorption studies are useful in the determination of catalyst surface area and pore size distribution

Answer

A higher temperature favours the reaction of higher activation energy

Question 5

The effectiveness factor for large value of Thiele modulus $${	ext{L}}\sqrt {{	ext{K}}/{{	ext{D}}_1}} $$ of a solid catalysed first order reaction is equal to (where, L = length of the reactor, cm, D1 = diffusion co-efficient, cm2/second)

Accepted Answer

$$\frac{1}{{{	ext{L}}\sqrt {{	ext{K}}/{{	ext{D}}_1}} }}$$

Answer

$${	ext{L}}\sqrt {{	ext{K}}/{{	ext{D}}_1}} $$

Answer

1

Answer

$$\infty $$

Question 6

The performance equations for constant density systems are identical for

Accepted Answer

P.F.R. and batch reactor

Answer

P.F.R. and backmix reactor

Answer

P.F.R, batch reactor and backmix reactor

Answer

Batch reactor and backmix reactor

Question 7

During manufacture of H2SO4, the oxidation of SO2 to SO3 by oxygen is an en-dothermic reaction. The yield of SO3 will be maximised, if the

Accepted Answer

Temperature is reduced and pressure is increased

Answer

Temperature is increased

Answer

Pressure is reduced

Answer

Temperature is increased and pressure is reduced

Question 8

__________ is the controlling step in a highly temperature sensitive fluid-solid non-catalytic reaction.

Accepted Answer

Chemical reaction

Answer

Gas film diffusion

Answer

Ash diffusion

Answer

None of these

Question 9

Space time in flow reactor is

Accepted Answer

Both A and B

Answer

Usually equal to the residence time

Answer

The reciprocal of the space velocity

Answer

A measure of its capacity