Chemical Reaction Engineering MCQs

65. Rate constant for a first order reaction does not depend upon reaction time, extent of reaction and the initial concentration of reactants ; but it is a function of reaction temperature. In a chemical reaction, the time required to reduce the concentration of reactant from 100 gm moles/litre to 50 gm moles/litre is same as that required to reduce it from 2 gm moles/litre to 1 gm mole/litre in the same volume. Then the order of this reaction is

by
0
1
2
3
✅ The correct answer is option B.

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.

by
(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

by
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.

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)

by
Tan hT/T
Tan T/T
Tan hT/tan T
None of these
✅ The correct answer is option A.