CHEMICAL REACTION ENGINEERING QUIZ

Half life period of decomposition of a liquid 'A' by irreversible first order reaction is 12 minutes. The time required for 75% conversion of 'A' is __________ minutes.

18

24

6

12

TRUE ANSWER : ?
YOUR ANSWER : ?

In case of the irreversible unimolecular type, first order reaction, the fractional conversion at any time for constant volume system as compared to variable volume system is

Same

Less

Either A or B, depends on other factors

More

TRUE ANSWER : ?
YOUR ANSWER : ?

For a tubular reactor with space time 'τ' and residence time 'θ', the following statement holds good.

τ = θ , when the fluid density changes in the reactor

τ = θ , for a non-isothermal reactor

τ and θ are always equal

τ = θ , for an isothermic tubular reactor in which the density of the process fluid is constant

TRUE ANSWER : ?
YOUR ANSWER : ?

Fluidised bed reactor is characterised by

Absence of continuous catalyst regeneration facility

Very small pressure drop

Uniformity of temperature

Comparatively smaller equipment

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YOUR ANSWER : ?

The ratio of moles of a reactant converted into the desired product to that converted into unwanted product is called

Selectivity

None of these

Relative yield

Operational yield

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YOUR ANSWER : ?

A space velocity of 5 hr⁻¹ means that

Five reactor volumes of feed (at specified conditions) are being fed into the reactor per hour

Cent per cent conversion can be achieved in at least 5 hours

A fixed conversion of a given batch of feed takes 5 hours

After every 5 hours, reactor is being filled with the feed

TRUE ANSWER : ?
YOUR ANSWER : ?

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

1

0

3

2

TRUE ANSWER : ?
YOUR ANSWER : ?

The reaction A → B is conducted in an isothermal batch reactor. If the conversion of A increases linearly with holding time, then the order of the reaction is

0

2

1.5

1

TRUE ANSWER : ?
YOUR ANSWER : ?

The rate of the heterogenous catalytic reaction A(g) + B(g) ? C(g) is given by -rA = k.KA.pA.PB/(1 + KA.PA + Kc.pc), where KA and Kc are the adsorption equilibrium constants. The rate controlling step for this reaction isA. absorption of A.

Surface reaction between A in the gas phase and absorbed B

Surface reaction between absorbed A and B in the gas phase

Surface reaction between absorbed A and absorbed B

Absorption of A

TRUE ANSWER : ?
YOUR ANSWER : ?

For the reaction, A + B → 2B + C,

rA = -rB

rA = 2rB

rA = rB

rA = rB/2

TRUE ANSWER : ?
YOUR ANSWER : ?