61. For the reaction, A + B → 2B + C,
rA = rB
rA = -rB
rA = 2rB
rA = rB/2
✅ The correct answer is option B.
Chemical Reaction Engineering MCQs
62. If a solid-gas non-catalytic reaction occurs at very high temperature, the rate controlling step is the __________ diffusion.
Film
Ash layer
Pore
None of these
✅ The correct answer is option A.
63. The most suitable reactor for carrying out an auto-thermal reaction is a
Batch reactor
CSTR
Semi-batch reactor
Plug-flow reactor
✅ The correct answer is option B.
64. The catalytic activity of enzymes is due to their capacity to lower the __________ energy.
Activation
Potential
Kinetic
None of these
✅ The correct answer is option A.
66. In the converter of the contact process for the manufacture of H₂SO₄ the equilibrium conversion of SO₂ __________ (i) __________ with increase in temperature and __________ (ii) __________ with increase in the mole ratio of SO₂ to air.
(i) increases (ii) decreases
(i) decreases (ii) increases
(i) increases (ii) increases
(i) decreases (ii) decreases
✅ The correct answer is option B.
67. A stirred tank reactor compared to tubular-flow reactor provides
More uniform operating conditions
Permits operation at the optimum temperature for a long reaction time
Higher overall selectivity for a first order consecutive reaction
All of the above
✅ The correct answer is option D.
68. The rate of a homogeneous reaction is a function of
Temperature and pressure only
Temperature and composition only
Pressure and composition only
All of the above
✅ The correct answer is option D.
69. Effectiveness factor (E) of a catalyst pellet is defined as, E = (actual rate within pore of catalyst/rate if notsnowed by pore diffusion) Effectiveness factor for a first order reaction is given by (where, T = Thiele modulus)
Tan hT/T
Tan T/T
Tan hT/tan T
None of these
✅ The correct answer is option A.
70. Half-life period for a first order reaction is __________ the initial concentration of the reactant.
Directly proportional to
Inversely proportional to
Independent of
None of these
✅ The correct answer is option C.