Month: February 2019

The effectiveness factor for large value of Thiele modulus [L√(K/D1)] of a solid catalysed first order reaction is equal to (where, L = length of the reactor, cm, D1 = diffusion co-efficient, cm2/second) ?

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The effectiveness factor for large value of Thiele modulus [L√(K/D1)] of a solid catalysed first order reaction is equal to (where, L = length of the reactor, cm, D1 = diffusion co-efficient, cm2/second) ?

A. L √(K/D1)
B. 1/[L√(K/D1)]
C. 1
D. ∞

The rate of an autocatalytic reaction as shown in the bellow figure, is given by – rA = k . CA . CB. In this case, the__________________?

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The rate of an autocatalytic reaction as shown in the bellow figure, is given by – rA = k . CA . CB. In this case, the__________________?

A. Plot of – rA Vs CA is a straight line with slope k
B. Plot of – rA Vs CA is a hyperbola
C. Rate of disappearance of reactant A is maximum, where CA = CB
D. Both B & C

The first order gas phase reaction as shown in the bellow figure is conducted isothermally in batch mode. The rate of change of conversion with time is given by________________?

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The first order gas phase reaction as shown in the bellow figure is conducted isothermally in batch mode. The rate of change of conversion with time is given by________________?

A. dXA/dt = k1 (1 – XA)2 (1 + 2XA)
B. dXA/dt = k1 (1 – XA) (1 + 0.5XA)
C. dXA/dt = k1 (1 – XA)
D. dXA/dt = k1 (1 – XA)/(1 + XA)

Three plug flow reactors (PFR’s) of 4, 5 & 6 m3 volumes are arranged in two branches as shown below in the figure. If the total feed rate is 300 tons/hr, then for the same conversion in each branch, the feed rate through branch II should be ______________ tons/hr ?

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Three plug flow reactors (PFR’s) of 4, 5 & 6 m3 volumes are arranged in two branches as shown below in the figure. If the total feed rate is 300 tons/hr, then for the same conversion in each branch, the feed rate through branch II should be ______________ tons/hr ?

A. 100
B. 150
C. 200
D. 225

An irreversible first order reaction is being carried out in a CSTR and PFR of same volume. The liquid flow rates are same. The relative conversion will__________________?

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An irreversible first order reaction is being carried out in a CSTR and PFR of same volume. The liquid flow rates are same. The relative conversion will__________________?

A. Be more in CSTR than in PFR
B. Be more in PFR than in CSTR
C. Be same in both cases
D. Depend on the temperature