Chemical Engineering - MCQ Practice Questions

In a plug flow reactor (PFR) processing a first-order irreversible reaction with rate constant k = 0.5 min⁻¹, what is the space-time (τ) required to achieve 80% conversion?

Which of the following statements about residence time distribution (RTD) is correct?

A CSTR operating at steady state processes an exothermic reaction. If the inlet temperature increases by 10°C while maintaining constant coolant flow rate, which parameter is most likely to increase?

For a reversible reaction A ⇌ B with equilibrium constant Ke = 4, what is the maximum theoretical conversion in a batch reactor at equilibrium?

In a semi-batch reactor where reactant A is fed continuously to a batch of reactant B, which advantage is realized?

The Damköhler number (Da) for a chemical reaction is defined as the ratio of:

A series of 3 identical CSTRs in cascade is used to process a first-order reaction with overall conversion X = 90%. Which statement is true?

In a fixed-bed catalytic reactor, what is the primary cause of catalyst deactivation by sintering?

For a second-order reaction in a PFR, increasing the inlet concentration while maintaining constant volumetric flow rate will result in:

Which reactor configuration would be best suited for a fast, highly exothermic reaction where precise temperature control is critical?

The Weisz-Prater criterion is used to determine:

In a membrane reactor for an equilibrium-limited reaction, what is the primary advantage?

The mean residence time in a reactor can be calculated from RTD data using:

For parallel reactions where A → B (desired) with rate constant k₁ and A → C (undesired) with rate constant k₂, the selectivity towards B is maximized by:

In the design of a CSTR for a reaction with Arrhenius parameters: Ea = 50 kJ/mol, A = 10⁵ s⁻¹, what is the approximate k at 50°C?

The conversion in a batch reactor at any time can be found by integrating the rate equation. For a first-order reaction, the half-life is:

In a tubular reactor with axial dispersion, increasing the Peclet number (Pe) results in:

For the reaction 2A + B → Products, if the reaction is 2nd order in A and 1st order in B, the rate equation is:

In a heterogeneous catalytic reaction, the overall rate is limited by which step if the external mass transfer coefficient is very small?

For a polymerization reaction in a batch reactor, the polydispersity index (PDI) and average molecular weight depend on: