Chemical Reaction Engineering interview questions

1. A.steady-state mole balance V/F_A0 = X/(−r_A) evaluated at outlet conditions, since the whole vessel sits at exit composition
2. B.rate constant rises exponentially with temperature as k = A·exp(−E/RT); activation energy comes from the slope of ln k against 1/T
3. C.time to consume half the reactant, equal to 0.693/k and independent of the initial concentration
4. D.exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors

Answer + AI explanation with Pro

1. A.Arrhenius equation
2. B.Space time
3. C.Damköhler number
4. D.Effectiveness factor

Answer + AI explanation with Pro

1. A.Arrhenius equation — ratio of actual rate in a catalyst pellet to the rate if the whole interior were at surface concentration; it falls as the Thiele modulus rises
2. B.Arrhenius equation — reactor volume divided by volumetric feed rate, the time needed to process one reactor volume of feed at inlet conditions
3. C.Arrhenius equation — condition where heat release outruns cooling so temperature and rate climb together; avoided by keeping the heat-removal line steeper than the heat-generation curve
4. D.Arrhenius equation — rate constant rises exponentially with temperature as k = A·exp(−E/RT); activation energy comes from the slope of ln k against 1/T

Answer + AI explanation with Pro

1. A.time to consume half the reactant, equal to 0.693/k and independent of the initial concentration
2. B.condition where heat release outruns cooling so temperature and rate climb together; avoided by keeping the heat-removal line steeper than the heat-generation curve
3. C.exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors
4. D.ratio of actual rate in a catalyst pellet to the rate if the whole interior were at surface concentration; it falls as the Thiele modulus rises

Answer + AI explanation with Pro

1. A.Thermal runaway
2. B.Half-life of a first-order reaction
3. C.Effectiveness factor
4. D.Arrhenius equation

Answer + AI explanation with Pro

1. A.Half-life of a first-order reaction — for a positive-order reaction a plug-flow reactor needs less volume than a mixed reactor at the same conversion because it works at higher average concentration
2. B.Half-life of a first-order reaction — ratio of actual rate in a catalyst pellet to the rate if the whole interior were at surface concentration; it falls as the Thiele modulus rises
3. C.Half-life of a first-order reaction — time to consume half the reactant, equal to 0.693/k and independent of the initial concentration
4. D.Half-life of a first-order reaction — rate constant rises exponentially with temperature as k = A·exp(−E/RT); activation energy comes from the slope of ln k against 1/T

Answer + AI explanation with Pro

1. A.reactor volume divided by volumetric feed rate, the time needed to process one reactor volume of feed at inlet conditions
2. B.ratio of actual rate in a catalyst pellet to the rate if the whole interior were at surface concentration; it falls as the Thiele modulus rises
3. C.steady-state mole balance V/F_A0 = X/(−r_A) evaluated at outlet conditions, since the whole vessel sits at exit composition
4. D.rate constant rises exponentially with temperature as k = A·exp(−E/RT); activation energy comes from the slope of ln k against 1/T

Answer + AI explanation with Pro

1. A.CSTR design equation
2. B.Space time
3. C.Residence time distribution
4. D.Effectiveness factor

Answer + AI explanation with Pro

1. A.Space time — exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors
2. B.Space time — time to consume half the reactant, equal to 0.693/k and independent of the initial concentration
3. C.Space time — ratio of reaction rate to convective transport rate; large values mean conversion is limited by transport rather than kinetics
4. D.Space time — reactor volume divided by volumetric feed rate, the time needed to process one reactor volume of feed at inlet conditions

Answer + AI explanation with Pro

1. A.time to consume half the reactant, equal to 0.693/k and independent of the initial concentration
2. B.for a positive-order reaction a plug-flow reactor needs less volume than a mixed reactor at the same conversion because it works at higher average concentration
3. C.exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors
4. D.condition where heat release outruns cooling so temperature and rate climb together; avoided by keeping the heat-removal line steeper than the heat-generation curve

Answer + AI explanation with Pro

1. A.Arrhenius equation
2. B.Space time
3. C.Damköhler number
4. D.CSTR vs PFR volume

Answer + AI explanation with Pro

1. A.CSTR vs PFR volume — ratio of reaction rate to convective transport rate; large values mean conversion is limited by transport rather than kinetics
2. B.CSTR vs PFR volume — steady-state mole balance V/F_A0 = X/(−r_A) evaluated at outlet conditions, since the whole vessel sits at exit composition
3. C.CSTR vs PFR volume — time to consume half the reactant, equal to 0.693/k and independent of the initial concentration
4. D.CSTR vs PFR volume — for a positive-order reaction a plug-flow reactor needs less volume than a mixed reactor at the same conversion because it works at higher average concentration

Answer + AI explanation with Pro

1. A.rate constant rises exponentially with temperature as k = A·exp(−E/RT); activation energy comes from the slope of ln k against 1/T
2. B.condition where heat release outruns cooling so temperature and rate climb together; avoided by keeping the heat-removal line steeper than the heat-generation curve
3. C.time to consume half the reactant, equal to 0.693/k and independent of the initial concentration
4. D.steady-state mole balance V/F_A0 = X/(−r_A) evaluated at outlet conditions, since the whole vessel sits at exit composition

Answer + AI explanation with Pro

1. A.CSTR design equation
2. B.Effectiveness factor
3. C.Thermal runaway
4. D.Space time

Answer + AI explanation with Pro

1. A.CSTR design equation — for a positive-order reaction a plug-flow reactor needs less volume than a mixed reactor at the same conversion because it works at higher average concentration
2. B.CSTR design equation — exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors
3. C.CSTR design equation — ratio of reaction rate to convective transport rate; large values mean conversion is limited by transport rather than kinetics
4. D.CSTR design equation — steady-state mole balance V/F_A0 = X/(−r_A) evaluated at outlet conditions, since the whole vessel sits at exit composition

Answer + AI explanation with Pro

1. A.time to consume half the reactant, equal to 0.693/k and independent of the initial concentration
2. B.for a positive-order reaction a plug-flow reactor needs less volume than a mixed reactor at the same conversion because it works at higher average concentration
3. C.exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors
4. D.ratio of reaction rate to convective transport rate; large values mean conversion is limited by transport rather than kinetics

Answer + AI explanation with Pro

1. A.Effectiveness factor
2. B.Residence time distribution
3. C.CSTR vs PFR volume
4. D.Damköhler number

Answer + AI explanation with Pro

1. A.Damköhler number — exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors
2. B.Damköhler number — for a positive-order reaction a plug-flow reactor needs less volume than a mixed reactor at the same conversion because it works at higher average concentration
3. C.Damköhler number — reactor volume divided by volumetric feed rate, the time needed to process one reactor volume of feed at inlet conditions
4. D.Damköhler number — ratio of reaction rate to convective transport rate; large values mean conversion is limited by transport rather than kinetics

Answer + AI explanation with Pro

1. A.time to consume half the reactant, equal to 0.693/k and independent of the initial concentration
2. B.exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors
3. C.condition where heat release outruns cooling so temperature and rate climb together; avoided by keeping the heat-removal line steeper than the heat-generation curve
4. D.steady-state mole balance V/F_A0 = X/(−r_A) evaluated at outlet conditions, since the whole vessel sits at exit composition

Answer + AI explanation with Pro

1. A.Residence time distribution
2. B.Arrhenius equation
3. C.Space time
4. D.Thermal runaway

Answer + AI explanation with Pro

1. A.Residence time distribution — steady-state mole balance V/F_A0 = X/(−r_A) evaluated at outlet conditions, since the whole vessel sits at exit composition
2. B.Residence time distribution — rate constant rises exponentially with temperature as k = A·exp(−E/RT); activation energy comes from the slope of ln k against 1/T
3. C.Residence time distribution — exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors
4. D.Residence time distribution — ratio of actual rate in a catalyst pellet to the rate if the whole interior were at surface concentration; it falls as the Thiele modulus rises

Answer + AI explanation with Pro

1. A.ratio of actual rate in a catalyst pellet to the rate if the whole interior were at surface concentration; it falls as the Thiele modulus rises
2. B.for a positive-order reaction a plug-flow reactor needs less volume than a mixed reactor at the same conversion because it works at higher average concentration
3. C.ratio of reaction rate to convective transport rate; large values mean conversion is limited by transport rather than kinetics
4. D.exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors

Answer + AI explanation with Pro

1. A.Thermal runaway
2. B.Damköhler number
3. C.CSTR design equation
4. D.Effectiveness factor

Answer + AI explanation with Pro

1. A.Effectiveness factor — time to consume half the reactant, equal to 0.693/k and independent of the initial concentration
2. B.Effectiveness factor — condition where heat release outruns cooling so temperature and rate climb together; avoided by keeping the heat-removal line steeper than the heat-generation curve
3. C.Effectiveness factor — ratio of actual rate in a catalyst pellet to the rate if the whole interior were at surface concentration; it falls as the Thiele modulus rises
4. D.Effectiveness factor — for a positive-order reaction a plug-flow reactor needs less volume than a mixed reactor at the same conversion because it works at higher average concentration

Answer + AI explanation with Pro

1. A.reactor volume divided by volumetric feed rate, the time needed to process one reactor volume of feed at inlet conditions
2. B.steady-state mole balance V/F_A0 = X/(−r_A) evaluated at outlet conditions, since the whole vessel sits at exit composition
3. C.ratio of reaction rate to convective transport rate; large values mean conversion is limited by transport rather than kinetics
4. D.condition where heat release outruns cooling so temperature and rate climb together; avoided by keeping the heat-removal line steeper than the heat-generation curve

Answer + AI explanation with Pro

1. A.CSTR vs PFR volume
2. B.Thermal runaway
3. C.Residence time distribution
4. D.Arrhenius equation

Answer + AI explanation with Pro

1. A.Thermal runaway — ratio of reaction rate to convective transport rate; large values mean conversion is limited by transport rather than kinetics
2. B.Thermal runaway — condition where heat release outruns cooling so temperature and rate climb together; avoided by keeping the heat-removal line steeper than the heat-generation curve
3. C.Thermal runaway — exit-age distribution E(t) from a tracer pulse, used to diagnose dead zones, bypassing and channelling in real reactors
4. D.Thermal runaway — steady-state mole balance V/F_A0 = X/(−r_A) evaluated at outlet conditions, since the whole vessel sits at exit composition

Answer + AI explanation with Pro