Chemical Engineering Archives

7691. The half life period of a first order reaction is

Always the same irrespective of the reaction

Dependent on initial concentration of the reactants

Proportional to the initial concentration of reactants

Half the specific rate constant

✅ The correct answer is option B.

7692. Fractional conversion __________ with increase in pressure for ammonia synthesis reaction i.e., N₂ + 3H₂ ⇋ 2NH₃.

Increases

Decreases

Remains unchanged

Unpredictable from the data

✅ The correct answer is option A.

7693. For reactions in parallel viz A → P (desired product) and A → Q (unwanted product), if the order of the desired reaction is higher than that of the undesired reaction, a

Batch reactor is preferred over a single CSTR for high yield

Tubular reactor is preferred over a single CSTR for high yield

Both A and B

Single CSTR is the most suitable

✅ The correct answer is option C.

7694. An example of autothermal reactor operation is

Sulphur dioxide oxidation

Ethylene oxidation

Benzene oxidation

Ammonia synthesis

✅ The correct answer is option B.

7695. The fractional volume change between no conversion and complete conversion, for the isothermal gas phase reaction, 2A → R, is

0.5

-0.5

1.5

✅ The correct answer is option B.

7696. The dispersion number of perfect mixed flow is

> 150

∞

< 2100

✅ The correct answer is option C.

7697. An endothermic aqueous phase first order irreversible reaction is carried out in an adiabatic plug flow reactor. The rate of reaction

Is maximum at the inlet of the reactor

Goes through a maximum along the length of the reactor

Goes through a minimum along the length of the reactor

Is maximum at the exit of the reactor

✅ The correct answer is option A.

7698. 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.

7699. 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.

7700. 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.