Chemical Reaction Engineering

Question: A pulse tracer is introduced in an ideal CSTR (with a mean residence time ι) at time, t = 0. The time taken for the exit concentration of the tracer to reach half of its initial value will be
[A].

2τ

[B].

0.5τ

[C].

τ/0.693

[D].

0.693τ

Answer: Option A

Explanation:

No answer description available for this question.

Question: An exothermic reaction takes place in an adiabatic reactor. The product temperature __________ reactor feed temperature.
[A].

is always equal to

[B].

is always greater than

[C].

is always less than

[D].

may be greater or less than

Answer: Option B

Explanation:

No answer description available for this question.

Question: For an ideal plug flow reactor, the value of Peclet number is
[A].

0

[B].

∞

[C].

1

[D].

10

Answer: Option A

Explanation:

No answer description available for this question.

Question: For a vapour phase catalytic reaction (A + B P) which follows the Ridel mechanism and the reaction step is rate controlling, the rate of reaction is given by (reaction rate is irreversible, product also absorbs).
[A].

[B].

[C].

[D].

Answer: Option A

Explanation:

No answer description available for this question.

Question: In solid catalysed reactions the diffusional effects are more likely to affect the overall rate of reaction for
[A].

fast reactions in catalyst of small pore diameter.

[B].

fast reaction in catalyst of large pore diameter.

[C].

slow reactions in catalyst of small pore diameter.

[D].

slow reactions in catalyst of large pore diameter.

Answer: Option C

Explanation:

No answer description available for this question.

Question: For the liquid phase parallel reactions:R, rR = K1.CA2; E1 = 80 KJ/moleS, rs= K1.CA ; E2 = 120 KJ/mole The desired product is R. A higher selectivity of R will be achieved, if the reaction is conducted at
[A].

low temperature in a CSTR.

[B].

high temperature in a CSTR.

[C].

low temperature in a PFR.

[D].

high temperature in a PFR.

Answer: Option D

Explanation:

No answer description available for this question.

Question: For the liquid phase zero order irreversible reaction A B, the conversion of A in a CSTR is found to be 0.3 at a space velocity of 0.1min-1 . What will be the conversion for a PFR with a space velocity of 0.2 min-1? Assume that all the other operating conditions are the same for CSTR and PFR.
[A].

0.15

[B].

0.30

[C].

0.60

[D].

0.90

Answer: Option C

Explanation:

No answer description available for this question.

Question: For the reversible reaction A 2B, if the equilibrium constant K is 0.05 mole/litre; starting from initially 2 moles of A and zero moles of B, how many moles will be formed at equilibrium ?
[A].

0.253

[B].

0.338

[C].

0.152

[D].

0.637

Answer: Option B

Explanation:

No answer description available for this question.

Question: An endothermic second order reaction is carried out in an adiabatic plug flow reactor. The rate of heat generation is
[A].

maximum at the inlet of the reactor.

[B].

maximum at the exit of the reactor.

[C].

maximum at the centre of the reactor.

[D].

constant throughout the reactor.

Answer: Option A

Explanation:

No answer description available for this question.

Question: For the reaction, A + B 2B + C,
[A].

rA = rB

[B].

rA = -rB

[C].

rA = 2rB

[D].

rA = rB/2

Answer: Option B

Explanation:

No answer description available for this question.