Chemical Engineering - MCQ Practice Questions

Which type of reactor provides the best conversion for a reversible exothermic reaction?

In a CSTR operating at steady state, if residence time is doubled and inlet concentration remains constant, how does conversion change for a first-order reaction?

For parallel reactions A→B and A→C, the selectivity of B over C is defined as:

In a catalytic reaction, which parameter does NOT affect the rate of reaction?

For the reaction 2A → B, if initial concentration of A is 2 mol/L and concentration after 5 minutes is 1 mol/L, calculate rate constant (assuming second-order):

The Damköhler number (Da) in chemical reactor design represents:

In enzyme catalysis, what does the Michaelis-Menten constant (K_m) represent?

For an exothermic reaction in an adiabatic reactor, what happens to the reaction rate as conversion increases?

For autocatalytic reactions, which reactor gives highest conversion at equilibrium?

For a second-order reaction A+B→C with equal initial concentrations of 1 mol/L, if the rate constant is 0.5 L/(mol·min), what is the time required for 50% conversion?

In a CSTR operating at steady state, the space time (τ) for a first-order reaction is 5 minutes. What is the conversion if k = 0.2 min⁻¹?

Which of the following reactor types is most suitable for producing fine chemicals where precise temperature control is critical?

In the Arrhenius equation k = A×e^(-Ea/RT), if the activation energy is 80 kJ/mol and temperature increases from 300K to 310K, what is the approximate ratio of rate constants k2/k1?

In a reversible elementary reaction A ⇌ B with forward rate constant kf = 0.1 s⁻¹ and reverse rate constant kr = 0.02 s⁻¹, what is the equilibrium constant K?

Which catalyst property is most important for industrial applications requiring high selectivity in parallel reactions?

For an exothermic reaction, operating a CSTR at higher conversion requires:

In industrial polymerization reactions, what is the primary role of chain termination reactions?

For a reaction A + B → C where both reactants are supplied in stoichiometric ratio, if reaction order with respect to A is 1 and B is 1, and initial concentrations are each 2 mol/L, the integrated rate law shows conversion X varies as:

Which of the following statements about residence time distribution (RTD) in reactors is incorrect?

For a first-order consecutive reaction A → B → C where k₁ = 0.1 min⁻¹ and k₂ = 0.05 min⁻¹, the maximum concentration of intermediate B occurs at approximately: