Reaction Engineering

Question 1

In which of the following cases does the reaction go farthest to completion?
a.k=102 c.k=10 b.k=10-2 d.k=1

Answer 1

A

Question 2

If “n” is the order of reaction, then unit of rate constant is
a. 1 / (time) (concentration)n-1
b. (time)-1(concentration)n-1
c. (time)n-1 (concentration)
d. none of these

Answer 2

A

Question 3

A certain reaction has a specific rate constant of 10 L/mol-min. The
order of the reaction is

Answer 3

2

Question 4

The reaction in which rate equation corresponds to a stoichiometric
equation is called

Answer 4

A

Question 5

The overall order of the reaction for the elementary reaction
A+2B -> C

Answer 5

3

Question 6

The rate of formation of B in terms of rA, where rA=-kCACB^2

Answer 6

2rA

Question 7

If the rate of reaction independent of the concentration of the reactants, the reaction is said to be?

Answer 7

0th order

Question 8

If the reaction, 2 A + B -> C is second order, which of the following plots will give a straight line?
a. log CA vs time c. log CA vs reciprocal time
b. CA vs time d.1/CA vs time

Answer 8

D

Question 9

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 the reaction
c. half of the residence time of the reaction
d. none of these

Answer 9

A

Question 10

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 the reaction
c. half of the residence time of the reaction
d. none of these

Answer 10

A

Question 11

The half-life of a material undergoing second order decay is
a. proportional to the square of initial concentration
b. independent of initial concentration
c. proportional to initial concentration
d. inversely proportional to initial concentration

Answer 11

D

Question 12

With increases in temperature, the rate constant obeying Arrhenius equation
a. increases
b. decreases
c. decreases exponentially with temperature
d. can either increase or decrease, depends on the frequency factor

Answer 12

A

Question 13

Which of the statements is wrong?
a. From Arrhenius Law, the value of the frequency factor, ko does affect the temperature sensitivity.
b. Reactions with high E are very T- sensitive, with low E are relatively T – insensitive
c. Any given reaction is much more T- sensitive at a low T than at a high T.
d. From Arrhenius law, a plot of ln k vs 1/T gives a straight line, with large slope for large E and small slope for small E.

Answer 13

A

Question 14

The equilibrium constant of a chemical reaction
a. increases in the presence of catalyst
b. decreases in the presence of catalyst
c. remains unaffected in the presence of a catalyst
d. can either increase or decrease; depends on the type of catalyst

Answer 14

C

Question 15

A batch reactor is characterized by
a. constant residence time
b. the variation in extent of reaction and properties of the reaction mixture with time
c. variation in reactor volume
d. very low conversion

Answer 15

B

Question 16

A plug-flow reactor is characterized by
a. high capacity
b. presence of axial mixing
c. presence of lateral mixing
d. constant composition and temperature of reaction mixture

Answer 16

C

Question 17

A backmix reactor
a. is same as plug-flow reactor
b. is same as ideal stirred tank reactor
c. employs mixing in axial direction only
d. is most suitable for gas phase reaction

Answer 17

B

Question 18

A space-time of 3 hours for a flow reactor means that
a. the time required to process one reactor volume of feed (measured
at specified conditions) is 3 hour
b. three reactor volumes of feed can be processed every hour
C. it takes three hours to dump the entire volume of the reaction with
feed
d. conversion is per cent after three hour

Answer 18

A

Question 19

A space velocity of 5/hour means that
a. five reactor volumes of feed (at specified conditions) are being fed
into the reactor per hour
b. after five hours, reactor is being filled with the feed
c. percent conversion can be achieved in at least 5 hours
d. a fixed conversion of a given batch of feed takes 5 hours

Answer 19

A

Question 20

For the reaction A + B → 2C, when CA is doubled, the rate doubles. When CB is doubled, the rate increases four folds. The rate law is

Answer 20

-rA = kCACB^2

Question 21

The cracking of crude oil is reaction.

Answer 21

HETEROGENEOUS CATALYTIC

Question 22

For an identical conversion and throughput, which of the reactors will have a larger volume if the reaction is second order?

a. backmix reactor
b. either of the two
c. cannot be determined
d. plug flow reactor

Answer 22

backmix

Question 23

Inversion of cane sugar is an example of

a. unimolecular reaction with second order
b. bimolecular reaction with first order
c. unimolecular reaction with first order
d. bimolecular reaction with second order

Answer 23

bimolecular reaction with first order

Question 24

Which of the following fixes the volume of a batch reactor for a particular conversion and production rate?

a. operating conditions
b. none of these
c. density of mixture
d. rate constant

Answer 24

c